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Chem. Proc., 2022, ECSOC 2022

The 26th International Electronic Conference on Synthetic Organic Chemistry

Online | 15–30 November 2022

Volume Editor:
Julio A. Seijas, Universidad of Santiago De Compostela, Spain

Number of Papers: 95
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Cover Story (view full-size image): This volume compiles the complete communications presented to the 26th International Conference on Synthetic Organic Chemistry together with the contributions of twelve keynote speakers, held online [...] Read more.
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4 pages, 527 KiB  
Proceeding Paper
Electrochemical Transformation of Bio-Derived Furans Using a Salen-Manganese Homogeneous Catalyst
Chem. Proc. 2022, 12(1), 1; https://doi.org/10.3390/ecsoc-26-13542 - 14 Nov 2022
Viewed by 923
Abstract
The electrochemical oxidation of HMF (5-hydroxymethylfurfural) to DMF (2,5-furandicarboxaldehyde) catalysed by a salen-manganese homogeneous catalyst is reported. DMF is a versatile precursor in the synthesis of functional polymers, pharmaceuticals, antifungal agents, and furan-urea resins. A manganese(III)-Schiff base complex 1 was synthetized and characterized [...] Read more.
The electrochemical oxidation of HMF (5-hydroxymethylfurfural) to DMF (2,5-furandicarboxaldehyde) catalysed by a salen-manganese homogeneous catalyst is reported. DMF is a versatile precursor in the synthesis of functional polymers, pharmaceuticals, antifungal agents, and furan-urea resins. A manganese(III)-Schiff base complex 1 was synthetized and characterized by different analytical and spectroscopic techniques. Complex 1 behaved as an efficient catalyst of the electrochemical oxidation of HMF to DMF. The conversion of HMF to DFF was performed under mild conditions. The oxidation of DFF to HMF with a conversion rate of 75% was achieved at pH 8.5, using sodium chloride as the electrolyte to increase the conductivity and to reduce the power dissipation. Full article
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6 pages, 891 KiB  
Proceeding Paper
In Vitro and In Silico Investigations of Natural Compounds with Predicted Activity against Neuroblastomas
Chem. Proc. 2022, 12(1), 2; https://doi.org/10.3390/ecsoc-26-13541 - 14 Nov 2022
Viewed by 789
Abstract
In the present study, the ability of an ethanolic extract from Stokesia laevis to inhibit the development of human glioblastoma cell line U87 has been investigated. Cytotoxic activity has been estimated at 78% in comparison to normal human astrocyte cell line NHA, while [...] Read more.
In the present study, the ability of an ethanolic extract from Stokesia laevis to inhibit the development of human glioblastoma cell line U87 has been investigated. Cytotoxic activity has been estimated at 78% in comparison to normal human astrocyte cell line NHA, while IC50 values were 9.12 μg of gallic acid ([GAE]) equivalents per 1 mL of extract for U87 and 24.17 μg of gallic acid ([GAE]) equivalents per 1 mL of extract for NHA. Docking simulations of the active compounds in Stokesia aster and curcumin against the target anti-apoptotic protein BCL-2 has revealed the following order in the magnitude of the docking scores: native ligand > curcumin > luteolin-7-O-glucoside > luteolin-8-O-glucoside > luteolin, with root mean square (RMS) between 0.01 and 0.93. Since neuroblastomas are not restricted by the blood–brain barrier and selective cytotoxicity has been demonstrated to be higher against tumor cells than normal control astrocytes, the use of Stokesia aster ethanolic extracts and luteolin derivates as an alternative approach to neuroblastomas is to be considered. Full article
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4 pages, 1148 KiB  
Proceeding Paper
An Unexpected Result of Base-Promoted Rearrangement of 4a-Acetyl-8a-hydroxydecahydroquinazoline-2-thione
Chem. Proc. 2022, 12(1), 3; https://doi.org/10.3390/ecsoc-26-13568 - 14 Nov 2022
Viewed by 823
Abstract
Treatment of 4a-acetyl-8a-hydroxydecahydroquinazoline-2-thione with NaH in acetonitrile leads to its isomerization into 1-hydroxy-1-methyl-3-thioxo-2,4-diazaspiro[5.5]undecan-7-one followed by the C1-C6 bond cleavage to give N-acetyl-N’-[(2-oxocyclohexyl)methyl]thiourea. The starting compound as a single diastereomer was prepared by the reaction between the K-enolate of 2-acetylcyclohexanone and [...] Read more.
Treatment of 4a-acetyl-8a-hydroxydecahydroquinazoline-2-thione with NaH in acetonitrile leads to its isomerization into 1-hydroxy-1-methyl-3-thioxo-2,4-diazaspiro[5.5]undecan-7-one followed by the C1-C6 bond cleavage to give N-acetyl-N’-[(2-oxocyclohexyl)methyl]thiourea. The starting compound as a single diastereomer was prepared by the reaction between the K-enolate of 2-acetylcyclohexanone and N-(tosylmethyl)thiourea or N-(azidomethyl)thiourea. Full article
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7 pages, 2382 KiB  
Proceeding Paper
“TYC” Reaction between Alkynes and Catechol-Thiol Derivatives Prompted by Metal Nanocatalysis: Mechanism Study by DFT Calculation
Chem. Proc. 2022, 12(1), 4; https://doi.org/10.3390/ecsoc-26-13588 - 15 Nov 2022
Viewed by 988
Abstract
A recently published article by our research group demonstrated that the hydrothiolation of activated alkynes is a successful way to functionalize thiols bearing catechols. The reaction was promoted by the CuNPs/TiO2 nanocatalyst and was regio- and stereoselective towards the anti-Markovnikov Z [...] Read more.
A recently published article by our research group demonstrated that the hydrothiolation of activated alkynes is a successful way to functionalize thiols bearing catechols. The reaction was promoted by the CuNPs/TiO2 nanocatalyst and was regio- and stereoselective towards the anti-Markovnikov Z-vinyl sulfide with good to excellent yields (47–97%). The scope of the reaction was evaluated and, based on experimental observations, the reaction mechanism was investigated through DFT studies. Theoretical results and experimental data were consistent with a reaction mechanism based on a copper-catalyzed anti-Markovnikov hydrothiolation process that favors the formation of the Z-vinyl sulfide. Full article
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10 pages, 1437 KiB  
Proceeding Paper
A Combined 2D- and 3D-QSAR Study, Design and Synthesis of Some Monocarbonyl Curcumin Analogs as Potential Inhibitors of MDA-MB-231 Breast Cancer Cells
Chem. Proc. 2022, 12(1), 5; https://doi.org/10.3390/ecsoc-26-13572 - 14 Nov 2022
Cited by 1 | Viewed by 1114
Abstract
Breast cancer is the most frequently diagnosed life-threatening cancer in women. As a result, there is a critical need for the development of a safe and effective drug therapy for its treatment. Curcumin, a secondary metabolite isolated from Curcuma longa, has been [...] Read more.
Breast cancer is the most frequently diagnosed life-threatening cancer in women. As a result, there is a critical need for the development of a safe and effective drug therapy for its treatment. Curcumin, a secondary metabolite isolated from Curcuma longa, has been shown to exhibit an impressively broad range of pharmacological effects. Despite its powerful interaction with a diverse set of cellular targets, curcumin has several drawbacks that limit its potential as a therapeutic agent. One of the most common approaches to overcoming these limitations is the design and synthesis of novel curcumin analogs. This study was conducted in support of the ongoing search for new molecules that are effective enough for the treatment of triple-negative breast cancer while causing only minor side effects. Hence, several symmetric monocarbonyl analogs of curcumin with cyclopentanone, cyclohexanone and 4-piperidone as the central core were synthesized via a Claisen–Schmidt condensation reaction. Their structures were identified by measuring the melting points, as well as using FTIR and UV/VIS spectroscopic techniques. To assess the cytotoxic activities of the analogs against MDA-MB-231 breast cancer cells and to identify the significant structural features responsible for these molecules’ potency, combined 2D- and 3D-quantitative structure–activity relationship (QSAR) models were developed. The generated QSAR models demonstrated acceptable internal validation, as well as good external predictive capacity, indicating that they can be used to design similar compounds. These results suggest that the synthesized candidate drugs have promising cytotoxic potential against MDA-MB-231 cancer cells and should be further investigated both in vitro and in vivo. Full article
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5 pages, 359 KiB  
Proceeding Paper
Reactions of exo-exo-hexacyclo[9.2.1.02,10.03,8.04,6.05,9]tetradecane with Aliphatic Alcohols under the Action of Ionic Liquids
Chem. Proc. 2022, 12(1), 6; https://doi.org/10.3390/ecsoc-26-13584 - 15 Nov 2022
Viewed by 864
Abstract
It has been established for the first time that ionic liquids catalyze the alcoholysis of a hydrogenated norbornadiene dimer—exo-exo-hexacyclo[9.2.1.02,10.03,8.04,6.05,9]tetradecane with aliphatic C1-C4 alcohols. The reaction proceeds along the hydrocarbon cyclopropane [...] Read more.
It has been established for the first time that ionic liquids catalyze the alcoholysis of a hydrogenated norbornadiene dimer—exo-exo-hexacyclo[9.2.1.02,10.03,8.04,6.05,9]tetradecane with aliphatic C1-C4 alcohols. The reaction proceeds along the hydrocarbon cyclopropane ring by a regioselective C4-C5 bond cleavage to form the previously undescribed 4-exo-alkoxypentacyclo[8.2.1.15,8.02,9.03,7]tetradecanes in high yields, which is promising as a precursor for the synthesis of drugs, as well as in the role of transmission media. Full article
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4 pages, 195 KiB  
Proceeding Paper
Distal Functionalization via Transition Metal Catalysis
Chem. Proc. 2022, 12(1), 7; https://doi.org/10.3390/ecsoc-26-13690 - 17 Nov 2022
Viewed by 949
Abstract
The ubiquitous presence of sp3 C−H bonds in natural feedstock makes them inexpensive, easily accessible, and attractive synthons for the preparation of common and/or complex molecular frameworks in biologically active natural products, pharmaceutics, agrochemicals, and materials. However, the inertness of these bonds [...] Read more.
The ubiquitous presence of sp3 C−H bonds in natural feedstock makes them inexpensive, easily accessible, and attractive synthons for the preparation of common and/or complex molecular frameworks in biologically active natural products, pharmaceutics, agrochemicals, and materials. However, the inertness of these bonds due to the high bond dissociation energies and low polarity difference between the carbon and hydrogen atoms makes them challenging reaction partners. Moreover, the desired site-selectivity is often an issue in reactions with multiple analogous sp3 C−H bonds. To overcome these problems, transition metal-catalyzed C−H functionalization has been developed with the assistance of various well-designed directing groups which can coordinate to a metal center to deliver it on a targeted C−H bond through an appropriate spatial arrangement, enabling C−H activation via the formation of a cyclometalated species. However, the frequent requirement of additional steps for the construction of the directing groups and their subsequent removal after the desired operation severely hampers the efficacy and compatibility of the reactions. A promising solution would be the utilization of a transient ligand which can bind to the substrate and coordinate to the metal center in a reversible fashion. In this way, the directing group is installed, sp3 C−H functionalization occurs, and the directing group is then removed in situ without affecting the substrate function after the catalysis is finished. Overall, the whole process occurs in a single reaction pot. Herein, we are presenting our studies on transition metal-catalyzed transient directing group-enabled C−H functionalization reaction. Full article
9 pages, 799 KiB  
Proceeding Paper
Synthesis, Spectral Characteristics, and Molecular Docking Studies of 2,4-Dichloro-N-(2,2,2-trichloro-1-((5-(phenylamino)-1,3,4-thiadiazol-2-yl)amino)ethyl)benzamide
Chem. Proc. 2022, 12(1), 8; https://doi.org/10.3390/ecsoc-26-13642 - 16 Nov 2022
Cited by 1 | Viewed by 1281
Abstract
Derivatives of 1,3,4-thiadiazole are of great interest for scientific and practical human activities as biologically active substances, dyes, components for creating semiconductors, energy accumulators, liquid crystals, polymers, nanomaterials, etc. Here we report the synthesis of 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(phenylamino)-1,3,4-thiadiazol-2-yl)amino)ethyl)benzamide based on N,N’ [...] Read more.
Derivatives of 1,3,4-thiadiazole are of great interest for scientific and practical human activities as biologically active substances, dyes, components for creating semiconductors, energy accumulators, liquid crystals, polymers, nanomaterials, etc. Here we report the synthesis of 2,4-dichloro-N-(2,2,2-trichloro-1-((5-(phenylamino)-1,3,4-thiadiazol-2-yl)amino)ethyl)benzamide based on N,N’-disubstituted hydrazinecarbothioamide—2,4-dichloro-N-(2,2,2-trichloro-1-(2-(phenylcarbamothioyl)-hydrazine-1-carbothioamido)ethyl)benzamide. The method for obtaining the target product is based on the dehydrosulfurization reaction of the starting hydrazinecarbothioamide under the action of a mixture of iodine and triethylamine in a DMF medium. A new derivative of 1,3,4-thiadiazole was obtained in 84% yield, and its structure was confirmed by 1H and 13C NMR spectroscopy data. Molecular docking studies were carried out with the structure of the resulting compound and dihydrofolate reductase (DHFR) in the AutoDock Vina program. The resulting compound is a potential inhibitor of DHFR and surpasses several known analogues in terms of the strength of the complex formed with the active site of this enzyme. Full article
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6 pages, 1211 KiB  
Proceeding Paper
Organophosphorus Chemistry: Synthesis of New Phosphonic Acid Derivatives Bearing a Triazole Moiety
Chem. Proc. 2022, 12(1), 9; https://doi.org/10.3390/ecsoc-26-13585 - 15 Nov 2022
Viewed by 1066
Abstract
A series of new 1,2,3-triazolylphosphonates were synthesized through multicomponent alkyne-azide 1,3-dipolar cycloaddition catalyzed by copper nanoparticles on activated carbon. The reactions were carried out in water and at a very low copper loading as green conditions, leading to the triazolylphosphonate products in moderate [...] Read more.
A series of new 1,2,3-triazolylphosphonates were synthesized through multicomponent alkyne-azide 1,3-dipolar cycloaddition catalyzed by copper nanoparticles on activated carbon. The reactions were carried out in water and at a very low copper loading as green conditions, leading to the triazolylphosphonate products in moderate to good yields. Studies into their activity as butyrylcholinesterase inhibitors are underway. Full article
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7 pages, 747 KiB  
Proceeding Paper
Synthetic Access to Tetracationic Benzoporphyrins and Their Role as Photosensitizers towards Gram-Negative Escherichia coli 
Chem. Proc. 2022, 12(1), 10; https://doi.org/10.3390/ecsoc-26-13587 - 15 Nov 2022
Viewed by 1051
Abstract
Currently, world population faces an episode where bacteria are becoming resistant to antibiotics, and it is crucial to find alternatives and new molecules to fight these microorganisms. Photodynamic inactivation of microorganisms has been pointed out as an alternative to conventional therapies. This work [...] Read more.
Currently, world population faces an episode where bacteria are becoming resistant to antibiotics, and it is crucial to find alternatives and new molecules to fight these microorganisms. Photodynamic inactivation of microorganisms has been pointed out as an alternative to conventional therapies. This work describes the synthesis of benzoporphyrins derivatives bearing triazolyl groups and of the analogues with pyridyl units under Heck coupling conditions. The benzoporphyrin derivatives containing pyridyl groups were further quaternized with iodomethane and 1-iodopentane to evaluate the influence of alkyl chain size on their photoinactivation ability. The biological studies towards Gram-negative Escherichia coli showed that the tetracationic benzoporphyrins can efficiently inactivate this bacterium. Full article
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8 pages, 1046 KiB  
Proceeding Paper
Carvacrol: A PLpro Inhibitor of SARS-CoV-2 Is a Natural Weapon for COVID-19
Chem. Proc. 2022, 12(1), 11; https://doi.org/10.3390/ecsoc-26-13679 - 17 Nov 2022
Viewed by 1817
Abstract
The outbreak of SARS-CoV-2 created the biggest crisis to human health and has adversely affected economic growth worldwide. Several vaccines emerged from manufacturers to combat COVID-19. Unfortunately, no therapeutic medication has yet been approved by the FDA for the treatment of this disease. [...] Read more.
The outbreak of SARS-CoV-2 created the biggest crisis to human health and has adversely affected economic growth worldwide. Several vaccines emerged from manufacturers to combat COVID-19. Unfortunately, no therapeutic medication has yet been approved by the FDA for the treatment of this disease. Many researchers have performed in silico studies for the identification of potential SARS-CoV-2 inhibitors from the molecules present in Indian medicinal plants and spices. In this paper, we have performed a structure-based virtual screening (VS) of 120 compounds derived from Nigella sativa (NS) against Mpro, PLpro, and spike proteins of SARS-CoV-2. Strong binding interactions of Mpro occurred with hits NS-40 and NS-84, whereas hits NS-72D and NS-95D showed strong binding interactions with spike proteins. Interestingly, four promising hits (i.e., NS-21, NS-40, carvacrol (NS_08), and menthol) exhibited good binding interactions with both Mpro and spike proteins. Carvacrol, a monoterpenoid phenol possessing several biological activities, showed a favourable binding affinity towards the papain-like protease of SARS-CoV-2. This small molecule may be used as a natural weapon to combat COVID-19. Full article
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7 pages, 1040 KiB  
Proceeding Paper
Conjugated Polymeric Liposomes: A Hybrid Carrier for Contemporary Drug Delivery
Chem. Proc. 2022, 12(1), 12; https://doi.org/10.3390/ecsoc-26-13640 - 16 Nov 2022
Viewed by 1157
Abstract
Liposomes are artificial vesicles encapsulating the drug moiety. The structural adaptability of liposomes has been employed to make them drug carriers for smart delivery systems, improving bioavailability, stability, target delivery, etc. However, conventional liposomes have some drawbacks, such as limited payload, shorter in [...] Read more.
Liposomes are artificial vesicles encapsulating the drug moiety. The structural adaptability of liposomes has been employed to make them drug carriers for smart delivery systems, improving bioavailability, stability, target delivery, etc. However, conventional liposomes have some drawbacks, such as limited payload, shorter in vivo circulatory lifespan, unregulated releasing properties, rapid clearance from bloodstream, etc. Polymeric modification of the liposomes addressed and effectively overcame all the drawbacks of conventional liposomes. Polymeric materials offer indefinite structural diversity, thus a substantial portion of the materials has been employed for drug-targeting methods and controlled drug release. Conjugation of liposomes and polymers develops a hybrid vesicle with intermediary physicochemical and stimulus responsive properties (pH, temperature, etc.). The reliability of liposomes with respect to pH, nature of drug moiety, enzyme, and immune response can be strengthened by polymers. Polymer modified liposomes also enhance the pharmacokinetic and pharmacodynamic profile of the drug moiety. The form of polymer, cross-linking agent, interaction, and bonding used during polymerized modification of liposomes all have an impact on their activity. According to the extensive review of the literature that is accessible in the different data sources, research in this field is proactively involved in the synthesis of newer polymeric materials, and the supramolecular structuring of the different chemicals. Full article
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10 pages, 2876 KiB  
Proceeding Paper
Construction of Lipid–Drug Conjugates for Beclomethasone Dipropionate
Chem. Proc. 2022, 12(1), 13; https://doi.org/10.3390/ecsoc-26-13528 - 14 Nov 2022
Viewed by 845
Abstract
Lipid-based nanoparticles (LBNs) are a new type of nanoparticulate drug-delivery system, which have gradually demonstrated broad prospects in pulmonary drug-delivery systems. However, the main disadvantage of these LBNs for inhalable drugs with limited lipophilicity is their low encapsulation capacity. Herein, this study anticipates [...] Read more.
Lipid-based nanoparticles (LBNs) are a new type of nanoparticulate drug-delivery system, which have gradually demonstrated broad prospects in pulmonary drug-delivery systems. However, the main disadvantage of these LBNs for inhalable drugs with limited lipophilicity is their low encapsulation capacity. Herein, this study anticipates establishing a technology platform to improve the loading capacity of low-lipophilicity drugs in LBNs for the therapy of lung diseases. A proof-of-concept study was carried out using Beclomethasone dipropionate (BDP) as a model drug. BDP was conjugated with stearic acid (SA), a kind of the lipid matrix for LBN. The conjugate was characterized and the interactions between the conjugate and SA were investigated via molecular dynamics simulation. It is expected that the drug-loading capacity of weak-lipophilic drugs in LBN can be increased by establishing the technology platform, and the application of LBNs in pulmonary delivery can be broadened. Full article
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4 pages, 506 KiB  
Proceeding Paper
Synthesis of N-Heterocyclic Carbene Gold Complexes Using 2,4,6-Trimethylphenyl Sydnone as Model Substrate
Chem. Proc. 2022, 12(1), 14; https://doi.org/10.3390/ecsoc-26-13674 - 17 Nov 2022
Viewed by 899
Abstract
Two gold(I) complexes have been synthesized by a two-step reaction. The first reaction step was the deprotonation with butyllithium to obtain the corresponding NHC. In the second reaction step, the metal precursor was added to afford the corresponding gold complex. At this point, [...] Read more.
Two gold(I) complexes have been synthesized by a two-step reaction. The first reaction step was the deprotonation with butyllithium to obtain the corresponding NHC. In the second reaction step, the metal precursor was added to afford the corresponding gold complex. At this point, the complex obtained depends on the nature of the metal precursor. A monocarbene complex (sydnone-Au-tht) was obtained using [Au(tht)Cl] as the metal precursor and a biscarbene complex (sydnone-Au-imidazolium) was obtained using a gold imidazolium complex as the metal precursor instead. The 13C-NMR resonance frequencies of the carbene carbon atom shifted to higher values from 97.3 to 135.6–139.7 ppm, mono and biscarbene, respectively. Full article
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7 pages, 802 KiB  
Proceeding Paper
Exploring BINOL-O-BODIPY-Based Dimers as Advanced Chromophoric Platforms Enabling Triplet State Population
Chem. Proc. 2022, 12(1), 15; https://doi.org/10.3390/ecsoc-26-13671 - 17 Nov 2022
Viewed by 1046
Abstract
An example of a new BODIPY design with triplet state population is reported: BINOL-O-BODIPY-based dimer. This new design combines two easily accessible structural features with a demonstrated capability of populating triplet states without the need for iodine or heavy metals: meso [...] Read more.
An example of a new BODIPY design with triplet state population is reported: BINOL-O-BODIPY-based dimer. This new design combines two easily accessible structural features with a demonstrated capability of populating triplet states without the need for iodine or heavy metals: meso-p-phenylene-bridged BODIPY dimer and BINOL-O-BODIPY. Full article
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5 pages, 1121 KiB  
Proceeding Paper
Synthesis and Chemosensory Studies of a Heterocyclic Thiosemicarbazone as a New Tributyltin Optical Chemosensor
Chem. Proc. 2022, 12(1), 16; https://doi.org/10.3390/ecsoc-26-13540 - 14 Nov 2022
Viewed by 796
Abstract
Thiosemicarbazones are a versatile type of organic compounds which are known for their coordination ability with different types of analytes, due to the presence of sulfur and nitrogen heteroatoms. Therefore, the functionalization of thiosemicarbazones with heterocyclic moieties can be a promising route to [...] Read more.
Thiosemicarbazones are a versatile type of organic compounds which are known for their coordination ability with different types of analytes, due to the presence of sulfur and nitrogen heteroatoms. Therefore, the functionalization of thiosemicarbazones with heterocyclic moieties can be a promising route to developing new optical chemosensors. Tributyltin (TBT) is an antifouling component of paints that is acutely toxic to aquatic environments, being quickly absorbed by microorganisms and causing problems such as imposex. Herein, the synthesis of a novel heterocyclic thiosemicarbazone, functionalized with a quinoline moiety, is reported to assess the potential of this recognition moiety for TBT optical chemosensing. A preliminary chemosensory study in acetonitrile solution was performed showing that 50 equivalents of TBT were needed to induce a change of color from colorless to yellow. Spectrophotometric titration was performed to assess the concentration of TBT necessary for a maximum optical signal, revealing that 100 equivalents of TBT were necessary to reach maximum absorbance, although it was able to respond with a detectable color change to a TBT concentration as low as 10 µM. Full article
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4 pages, 367 KiB  
Proceeding Paper
Structure-Property Influence on the Amphiphilicity of Phenolipids
Chem. Proc. 2022, 12(1), 17; https://doi.org/10.3390/ecsoc-26-13533 - 14 Nov 2022
Cited by 1 | Viewed by 732
Abstract
In recent years, increasing interest has been observed in phenolipids used for enhancing the quality of products containing lipids in the food, pharmaceutical and cosmetic industries. A better understanding of the physicochemical properties of these amphiphilic compounds is crucial to maximizing their antioxidant [...] Read more.
In recent years, increasing interest has been observed in phenolipids used for enhancing the quality of products containing lipids in the food, pharmaceutical and cosmetic industries. A better understanding of the physicochemical properties of these amphiphilic compounds is crucial to maximizing their antioxidant and antiproliferation properties. Therefore, certain p-hydroxycinnamic acid derivatives were synthesized and their lipophilicity expressed as a partition coefficient (Log P) was measured using the shake-flask method. Additionally, the obtained results were compared with the calculated data in ALOGPS 2.1. An increase in lipophilicity was observed along with an increased alkyl chain length. Moreover, hydrophilic/hydrophobic properties are closely related with the number of substituents, especially the hydroxyl group, in aromatic rings. Full article
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8 pages, 373 KiB  
Proceeding Paper
Phytochemistry of Uvaria narum: A Multifaceted Perspective and Ethnopharmacological Potential
Chem. Proc. 2022, 12(1), 18; https://doi.org/10.3390/ecsoc-26-13670 - 17 Nov 2022
Cited by 2 | Viewed by 1166
Abstract
The blooming ethnomedicinal plant Uvaria narum (Dunal) Wall is mostly found in the deep forests of the Western Ghats and belongs to the Annonaceae family. Uvaria narum is a spreading, pubescent shrub with large, dark bluish-green leaves. Phytochemistry and pharmacognostic studies have revealed [...] Read more.
The blooming ethnomedicinal plant Uvaria narum (Dunal) Wall is mostly found in the deep forests of the Western Ghats and belongs to the Annonaceae family. Uvaria narum is a spreading, pubescent shrub with large, dark bluish-green leaves. Phytochemistry and pharmacognostic studies have revealed that the plant possesses a variety of phytochemicals that are remarkable and beneficial to humans. The plant also possesses a number of beneficial properties, such as antioxidant activity exhibited by the presence of polyphenols and tannins, antifungal activity brought on by the benzoic acid moiety, and tumour-fighting ability contributed by terpenoid and alkaloids. The presence of phytoconstituents in the plant has been attributed to the various medicinal properties of the plant, such as anticancer activity. The plant may also be considered for use against ageing and other diseases caused by free radicals. In vitro cytotoxicity is due to terpenoids, phytosterols, and flavonoids, whereas the liver is protected by flavonoids. The chemical profile of the plant shows that acetogenins, including stereoisomers, are important constituents of the root bark. Eczema, itching, varicose veins, haemorrhoids, jaundice, inflammation, and fever are the main ailments for which this herb is used. Full article
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6 pages, 1326 KiB  
Proceeding Paper
Development of New Effective Methods for the Synthesis of Lembehynes A–C Exhibiting Cytotoxic and Neuritogenic Activity
Chem. Proc. 2022, 12(1), 19; https://doi.org/10.3390/ecsoc-26-13524 - 14 Nov 2022
Viewed by 728
Abstract
This report presents data on our studies on the preparation of the precursor lembehyne A and the complete stereoselective synthesis of natural lembehynes B and C, which have cytotoxic and neuritogenic activity. All methods and approaches to the synthesis of the above-mentioned lembehynes [...] Read more.
This report presents data on our studies on the preparation of the precursor lembehyne A and the complete stereoselective synthesis of natural lembehynes B and C, which have cytotoxic and neuritogenic activity. All methods and approaches to the synthesis of the above-mentioned lembehynes presented in this report are based on the use of the catalytic cross-cyclomagnesiation of 1,2-dienes (Dzhemilev reaction) at the key stage of the synthesis. Full article
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17 pages, 5855 KiB  
Proceeding Paper
Aromatic Iodides: Synthesis and Conversion to Heterocycles
Chem. Proc. 2022, 12(1), 20; https://doi.org/10.3390/ecsoc-26-13641 - 16 Nov 2022
Viewed by 1283
Abstract
Aromatic heterocycles can be found in many molecules endowed with specific properties, in particular for applications in the fields of medicinal chemistry and materials science. In this group, we notably develop synthetic methodologies to selectively introduce iodine onto aromatic compounds and to use [...] Read more.
Aromatic heterocycles can be found in many molecules endowed with specific properties, in particular for applications in the fields of medicinal chemistry and materials science. In this group, we notably develop synthetic methodologies to selectively introduce iodine onto aromatic compounds and to use this heavy halogen in order to build heterocycles of interest. While we sometimes employed direct iodinations on electron-enriched aromatic compounds, we mainly optimized deprotometallation–iodolysis sequences to functionalize substrates sensitive to nucleophilic attacks. In particular, hindered lithium amide–metal trap tandems have been designed to overcome the low tolerance of some functional groups (e.g., ketones or sensitive diazines) toward organolithiums. The aromatic iodides generated in these ways have been involved in transition metal–catalyzed cross-couplings to access original scaffolds (oxazoloquinoxalines, pyrazinoisatins, pyrazinocarbazoles, etc.). We specifically developed the use of aromatic iodides in the copper-mediated N-arylation of anilines, e.g., to reach triarylamines. Combined with subsequent cyclizations, these reactions allowed access to numerous heterocyclic compounds (such as acridones, acridines, other aza-aromatic polycycles and helicene-like structures) with potential applications. From some of the scaffolds obtained, biological evaluation in the frame of collaborations allowed properties of interest to be discovered (e.g., specific inhibition of protein kinases GSK-3 or PIM, related to cancer development). Full article
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10 pages, 2308 KiB  
Proceeding Paper
In-Silico Approaches for Molecular Characterization and Structure-Based Functional Annotation of the Matrix Protein from Nipah henipavirus 
Chem. Proc. 2022, 12(1), 21; https://doi.org/10.3390/ecsoc-26-13522 - 14 Nov 2022
Cited by 5 | Viewed by 1951
Abstract
Nipah henipavirus is an emerging RNA virus that poses a danger to world safety due to its high fatality rate. The Nipah virus has caused several illness epidemics in South and Southeast Asia. The matrix protein of Nipah henipavirus plays a crucial function [...] Read more.
Nipah henipavirus is an emerging RNA virus that poses a danger to world safety due to its high fatality rate. The Nipah virus has caused several illness epidemics in South and Southeast Asia. The matrix protein of Nipah henipavirus plays a crucial function in linking the viral envelope to the virus core. Connecting the viral envelope to the virus core is critical for virus assembly. Through analyses of structural and functional protein explanations, bioinformatics tools can aid in our comprehension of the protein. This study intends to provide structural and functional annotations to proteins. Using in silico approaches, the analysis also assigns the protein’s physicochemical properties, three-dimensional structure, and functional annotation. The in silico research validated the protein’s hydrophilic nature and alpha (α) helix-dominated secondary structure. The protein’s tertiary structure model is generally consistent based on various quality evaluation approaches. The functional explanation claimed that the protein is a structural protein that connects the viral envelope to the virus core, a protein that is necessary for virus assembly. This study reveals the importance of the matrix protein as a functional protein needed by Nipah henipavirus. Full article
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4 pages, 1107 KiB  
Proceeding Paper
Synthesis of Bis (1,4-Disubstituted-1,2,3-triazoles) Starting from Diethyl Galactarate
Chem. Proc. 2022, 12(1), 22; https://doi.org/10.3390/ecsoc-26-13689 - 17 Nov 2022
Viewed by 801
Abstract
This communication reports the synthesis of a series of bis (1,4-disubstituted-1,2,3-triazoles) starting from the known (2,3,4,5) bis acetonide-protected diethyl galactarate (1). Reduction of 1 with LiAlH4 led to dioxolane 2 (90%), which, upon treatment with CBr4, gave the [...] Read more.
This communication reports the synthesis of a series of bis (1,4-disubstituted-1,2,3-triazoles) starting from the known (2,3,4,5) bis acetonide-protected diethyl galactarate (1). Reduction of 1 with LiAlH4 led to dioxolane 2 (90%), which, upon treatment with CBr4, gave the corresponding dibromide 3 (80%). The reaction of 3 with NaN3 in DMF afforded the key diazide 4 (95%). From the diazide 4 were obtained the bis (1,4-disubstituted-1,2,3 triazoles) 58 via click reactions with alkyl-substituted acetylenes, including triphenyltinacetylene. The physical characteristics of the new compounds, including selected values of 1H, 13C, and 119Sn NMR data, are given. Full article
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5 pages, 1820 KiB  
Proceeding Paper
Expression of β-Catenin Marker in Colorectal Cancer Cells after Treatment with Royal Jelly
Chem. Proc. 2022, 12(1), 23; https://doi.org/10.3390/ecsoc-26-13531 - 14 Nov 2022
Viewed by 775
Abstract
The deregulation of a Wnt/β-catenin signal pathway is common in colorectal cancer, while β-catenin, its crucial component, is the target for the development of many anticancer therapies. Here, we showed that royal jelly, as a well-known beneficial natural product, can affect β-catenin at [...] Read more.
The deregulation of a Wnt/β-catenin signal pathway is common in colorectal cancer, while β-catenin, its crucial component, is the target for the development of many anticancer therapies. Here, we showed that royal jelly, as a well-known beneficial natural product, can affect β-catenin at both the gene and protein level in HCT-116 colorectal cancer cell line. Our results indicate the effectiveness of royal jelly in targeting crucial markers responsible for the development and progression of cancer. Therefore, royal jelly presents a promising agent for the development of supplementary anticancer therapy. Full article
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6 pages, 723 KiB  
Proceeding Paper
Semisynthesis of 6β-Acetoxyvouacapane Derivatives via the Ugi-Azide Multicomponent Reaction
Chem. Proc. 2022, 12(1), 24; https://doi.org/10.3390/ecsoc-26-13552 - 14 Nov 2022
Viewed by 784
Abstract
A semisynthesis of 6β-acetoxyvouacapane-1,5-disusbtituted tetrazoles derivatives from the leaves of Caesalpinia platyloba by using the Ugi-azide multicomponent reaction as a key step reaction is described. To our knowledge, this is the first report where a non-natural product such as 1,5-disusbtituted tetrazole [...] Read more.
A semisynthesis of 6β-acetoxyvouacapane-1,5-disusbtituted tetrazoles derivatives from the leaves of Caesalpinia platyloba by using the Ugi-azide multicomponent reaction as a key step reaction is described. To our knowledge, this is the first report where a non-natural product such as 1,5-disusbtituted tetrazole has been linked to a natural product or derivate of a natural product, and beyond the biological relevance that the target molecules present, this work contributes to the area of natural products as well as multicomponent reactions. Full article
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11 pages, 4809 KiB  
Proceeding Paper
Sulfur-Containing Homo- and Methanofullerenes: Synthesis and Study of Tribological Properties
Chem. Proc. 2022, 12(1), 25; https://doi.org/10.3390/ecsoc-26-13537 - 14 Nov 2022
Viewed by 815
Abstract
The data obtained by the authors in the field of carbon cluster chemistry, namely the catalytic cycloaddition of sulfur-containing diazo compounds to C60-fullerene under the action of complex Pd catalysts, are summarized. Cycloaddition reactions of diazoalkanes, diazoketones, and diazothioates with C [...] Read more.
The data obtained by the authors in the field of carbon cluster chemistry, namely the catalytic cycloaddition of sulfur-containing diazo compounds to C60-fullerene under the action of complex Pd catalysts, are summarized. Cycloaddition reactions of diazoalkanes, diazoketones, and diazothioates with C60-fullerene, catalyzed by Pd(acac)2–PPh3–Et3Al, with the selective formation of new sulfur-containing methano-, homo-, and pyrazolinofullerenes, are promising as modern nanosized additives in oils for highly loaded mechanisms. Full article
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6 pages, 1307 KiB  
Proceeding Paper
Synthesis and Evaluation of an Azo Dye for the Chromogenic Detection of Metal Cations
Chem. Proc. 2022, 12(1), 26; https://doi.org/10.3390/ecsoc-26-13556 - 14 Nov 2022
Viewed by 1266
Abstract
A carboxylic acid azo dye, Dabcyl, was synthesized and evaluated as a colorimetric chemosensor for metal cations with biological and environmental importance. The dye was prepared in high yield and characterized by 1H and 13C NMR and UV–Vis absorption spectroscopies. A [...] Read more.
A carboxylic acid azo dye, Dabcyl, was synthesized and evaluated as a colorimetric chemosensor for metal cations with biological and environmental importance. The dye was prepared in high yield and characterized by 1H and 13C NMR and UV–Vis absorption spectroscopies. A preliminary chemosensing study showed that Dabcyl displayed a marked color change from light yellow to pink, for Hg2+, Fe2+, Pd2+, Sn2+ and Al3+ in acetonitrile solution. Consequently, spectrophotometric titrations were carried out for this dye with selected cations, which clearly indicated that Dabcyl has potential application as a chromogenic probe for the cations under study with remarkable sensitivity and with a marked color change. Full article
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5 pages, 372 KiB  
Proceeding Paper
Modified Algar–Flynn–Oyamada Reaction for the Synthesis of 3-Hydroxy-2-styryl-chromen-4-ones under Solvent-Free Conditions
Chem. Proc. 2022, 12(1), 27; https://doi.org/10.3390/ecsoc-26-13558 - 14 Nov 2022
Viewed by 950
Abstract
The simple and efficient conditions for a Algar–Flynn–Oyamada reaction for the synthesis of 3-hydroxy-2-styryl-chromen-4-ones involving the grinding of different 1-(2′-hydroxy-phenyl)-5-aryl-penta-2,4-dien-1-ones with UHP (urea–hydrogen peroxide), pulverized potassium hydroxide and a few drops of ethanol at room temperature under solvent-free conditions are described. A presented [...] Read more.
The simple and efficient conditions for a Algar–Flynn–Oyamada reaction for the synthesis of 3-hydroxy-2-styryl-chromen-4-ones involving the grinding of different 1-(2′-hydroxy-phenyl)-5-aryl-penta-2,4-dien-1-ones with UHP (urea–hydrogen peroxide), pulverized potassium hydroxide and a few drops of ethanol at room temperature under solvent-free conditions are described. A presented protocol offers a faster reaction and a higher yield compared to conventional methods. The structure of the synthesized compounds was identified from their spectral data (IR, 1H-NMR). Full article
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11 pages, 1403 KiB  
Proceeding Paper
Preparation and Hydro-Lipophilic Properties of Monosubstituted N-Aryl-4-hydroxyquinoline-3-carboxanilides
Chem. Proc. 2022, 12(1), 28; https://doi.org/10.3390/ecsoc-26-13548 - 14 Nov 2022
Viewed by 769
Abstract
A series of twenty-two monosubstituted N-aryl-4-hydroxyquinoline-3-carboxanilides designed as dual anti-invasive agents was prepared and characterized. Lipophilicity significantly affects biological activities of compounds and ADME properties; therefore, the lipo-hydrophilic properties of these 4-hydroxyquinoline-3-carboxanilides were investigated. All the derivatives were analyzed using reversed-phase high-performance [...] Read more.
A series of twenty-two monosubstituted N-aryl-4-hydroxyquinoline-3-carboxanilides designed as dual anti-invasive agents was prepared and characterized. Lipophilicity significantly affects biological activities of compounds and ADME properties; therefore, the lipo-hydrophilic properties of these 4-hydroxyquinoline-3-carboxanilides were investigated. All the derivatives were analyzed using reversed-phase high-performance liquid chromatography. The procedure was carried out under isocratic conditions with methanol as the organic modifier in the mobile phase using an end-capped non-polar C18 stationary reversed-phase column. In this study, correlations between the logarithm of the capacity factor k and log P/Clog P values calculated using various methods are discussed, as well as the relationships between lipophilicity and chemical structure of the studied compounds. Full article
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6 pages, 3861 KiB  
Proceeding Paper
Computational Revision of the Mechanism of the Thorpe Reaction
Chem. Proc. 2022, 12(1), 29; https://doi.org/10.3390/ecsoc-26-13550 - 14 Nov 2022
Viewed by 1095
Abstract
The Thorpe reaction is described as a self-condensation of nitriles in the presence of a basic catalyst producing β-enaminonitriles. We performed theoretical calculations within the Density Functional Theory (DFT) framework at the ωB97XD/def2-svpd level to explore different mechanistic proposals when propionitrile is used [...] Read more.
The Thorpe reaction is described as a self-condensation of nitriles in the presence of a basic catalyst producing β-enaminonitriles. We performed theoretical calculations within the Density Functional Theory (DFT) framework at the ωB97XD/def2-svpd level to explore different mechanistic proposals when propionitrile is used as a reagent and sodium ethoxide (EtONa) as a catalyst. Furthermore, the influence of different solvents, such as ethanol (EtOH), tetrahydrofuran (THF), 1,2-dimethoxyethane (DME), and propionitrile (EtCN), was assessed. Finally, we also evaluated the effect of the fluorine group (-F), compared to the methyl group (-CH3), substituted in the α position of acetonitrile (MeCN). Our theoretical findings agree with different experimental reports on the Thorpe reaction. Full article
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5 pages, 885 KiB  
Proceeding Paper
Rearrangement of Imidazolidine to Piperazine Rings in the Presence of DyIII
Chem. Proc. 2022, 12(1), 30; https://doi.org/10.3390/ecsoc-26-13547 - 14 Nov 2022
Viewed by 702
Abstract
The formation of imidazolidines from secondary amines and aldehydes is well known. This small cycle can act as a nitrogen donor, and it is usually stable when it coordinates to metal ions. Sometimes, imidazolidines acting as ligands undergo breaking of the C-N bond [...] Read more.
The formation of imidazolidines from secondary amines and aldehydes is well known. This small cycle can act as a nitrogen donor, and it is usually stable when it coordinates to metal ions. Sometimes, imidazolidines acting as ligands undergo breaking of the C-N bond when coordinating to the metal center, yielding related amines. However, the reorganization of the imidazolidine into a piperazine ring is quite an unusual process. In this work, we describe the transformation of a zinc complex with a ligand containing two imidazolidine moieties into a zinc complex with a piperazine fragment as donor, in the presence of a dysprosium salt. Full article
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6 pages, 999 KiB  
Proceeding Paper
Use of Oxidative Coupling Strategy as a Means to Increase In Vitro Antioxidant Activity of Vanillin Derivatives
Chem. Proc. 2022, 12(1), 31; https://doi.org/10.3390/ecsoc-26-13553 - 14 Nov 2022
Cited by 1 | Viewed by 736
Abstract
The aim of this study was to investigate the antioxidant properties in vitro of three different vanillic dimmers (Compounds 1a–c). They were synthesized through an oxidative coupling strategy in good yields. The targeted compounds were found to be highly active for the [...] Read more.
The aim of this study was to investigate the antioxidant properties in vitro of three different vanillic dimmers (Compounds 1a–c). They were synthesized through an oxidative coupling strategy in good yields. The targeted compounds were found to be highly active for the total antioxidant assay, as well as for the lipid peroxidation test. All investigated compounds exhibited superior or comparable antioxidant capacity in comparison to precursor vanillin, proving that oxidative coupling is a great strategy to increase the antioxidant behavior of vanillin derivatives. Full article
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10 pages, 2287 KiB  
Proceeding Paper
Computational Approaches for Structure-Based Molecular Characterization and Functional Annotation of the Fusion Protein of Nipah henipavirus
Chem. Proc. 2022, 12(1), 32; https://doi.org/10.3390/ecsoc-26-13530 - 14 Nov 2022
Cited by 2 | Viewed by 1187
Abstract
Throughout history, viral epidemics of varying frequency and intensity have been responsible for inducing panic and causing widespread damage. The Nipah virus has one of the highest rates of fatalities of any infectious disease in the world. There have been cases when severe [...] Read more.
Throughout history, viral epidemics of varying frequency and intensity have been responsible for inducing panic and causing widespread damage. The Nipah virus has one of the highest rates of fatalities of any infectious disease in the world. There have been cases when severe respiratory distress has resulted in death, and it is known that these cases can cause encephalitis. The appearance of the virus and its ability to spread are affected by several factors. Several strategies have been created to raise awareness about the need for personal hygiene and enhance surveillance within the contaminated zone. This work aimed to determine the characteristics of a previously unidentified protein linked with the fusion of Nipah henipavirus particles. The protein’s secondary structure comprises helix, sheet, turn, and secondary coil structures. The protein is a fusion protein. In addition, the estimated Ramachandran plot provided evidence of the accuracy of the modeled protein structure. This accuracy was then verified by the Z-score-based and local model quality evaluation methods. It is possible to think of the protein as a target for developing prospective therapeutic and vaccine candidates directed against the protein to fight viral infections. Full article
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8 pages, 3541 KiB  
Proceeding Paper
DFT Studies on the Allylation of Styrene Oxide Catalyzed by Indium Nanoparticles (InNPs)
Chem. Proc. 2022, 12(1), 33; https://doi.org/10.3390/ecsoc-26-13545 - 14 Nov 2022
Viewed by 764
Abstract
Allyl–indium species are known to smoothly react with electrophiles as epoxides. The intrinsic tension of these cyclic systems makes them very reactive starting materials, giving access to more complex products through regioselective ring-opening. In this work, indium nanoparticles (InNPs) were prepared by fast [...] Read more.
Allyl–indium species are known to smoothly react with electrophiles as epoxides. The intrinsic tension of these cyclic systems makes them very reactive starting materials, giving access to more complex products through regioselective ring-opening. In this work, indium nanoparticles (InNPs) were prepared by fast reduction of indium(III) chloride with lithium sand and a catalytic amount of 4,4′-di-tert-butylbiphenyl. InNPs were employed as catalysts for the ring-opening allylation reaction of styrene oxide with allyl or prenylbromide. All the possible reaction paths for the formation of the different alcohols were modeled applying DFT calculations, achieving good correlation between the experimental and computational results. Full article
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5 pages, 510 KiB  
Proceeding Paper
Nickel-Catalyzed, One-Pot Synthesis of Pyrazoles
Chem. Proc. 2022, 12(1), 34; https://doi.org/10.3390/ecsoc-26-13687 - 17 Nov 2022
Viewed by 952
Abstract
Recently, multi-component, one-pot reactions have been shown to be efficient and environmentally friendly methods compared to traditional, linear-step syntheses. Heterogeneous catalyzed multicomponent reactions are one of the green approaches to the synthesis of organic compounds, especially pyrazoles and their derivatives. Here we demonstrate [...] Read more.
Recently, multi-component, one-pot reactions have been shown to be efficient and environmentally friendly methods compared to traditional, linear-step syntheses. Heterogeneous catalyzed multicomponent reactions are one of the green approaches to the synthesis of organic compounds, especially pyrazoles and their derivatives. Here we demonstrate the one-pot synthesis of pyrazoles using heterogeneous nickel-based catalysts for the condensation of various hydrazine, ketone derivatives, and aldehyde derivatives at room temperature. The thus synthesized heterogeneous catalyst can be reused up to the seventh cycle without much loss of catalytic activity. Full article
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5 pages, 1299 KiB  
Proceeding Paper
Cyclopalladated Compounds with Bulky Phosphine (dppm): Synthesis, Characterization, and X-ray Diffraction
Chem. Proc. 2022, 12(1), 35; https://doi.org/10.3390/ecsoc-26-13563 - 14 Nov 2022
Viewed by 809
Abstract
The reaction between a cholro-bridged dinuclear compound (a, b) and a diphosphine (dppm) ligand in a molar ratio of 1:2 yielded a mononuclear compound [{Pd[R-C6H3C(H)=NCy]{Ph2PCH2PPh2-P,P}][PF6] {R = 3-CHO (1a), 4-CHO (1b)}. [...] Read more.
The reaction between a cholro-bridged dinuclear compound (a, b) and a diphosphine (dppm) ligand in a molar ratio of 1:2 yielded a mononuclear compound [{Pd[R-C6H3C(H)=NCy]{Ph2PCH2PPh2-P,P}][PF6] {R = 3-CHO (1a), 4-CHO (1b)}. The compounds were characterized using IR, 1H, and 31P–{1H} NMR spectroscopy, and compound 1b was identified using X-ray diffraction. Full article
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10 pages, 4137 KiB  
Proceeding Paper
The Potential of Thiazole Derivatives as Antimicrobial Agents
Chem. Proc. 2022, 12(1), 36; https://doi.org/10.3390/ecsoc-26-13673 - 17 Nov 2022
Cited by 1 | Viewed by 2160
Abstract
A transnational concern for the healthy development of human beings is antimicrobial resistance (AMR). The rising rates of microbial resistance present a serious issue for the development of human life and hence it is essential to find and create newer antimicrobial drugs with [...] Read more.
A transnational concern for the healthy development of human beings is antimicrobial resistance (AMR). The rising rates of microbial resistance present a serious issue for the development of human life and hence it is essential to find and create newer antimicrobial drugs with unique modes of action. One approach used these days to solving this challenge is the use of heterocyclics to create hybrid compounds by fusing two or more bioactive heterocyclic moieties into a single molecular platform. This study discusses the many hybrid approaches that have been used to produce possible novel antimicrobial medicines that are both safe and effective. The landscaping of heterocycles such as thiazole derivatives is covered in the current review paper. In this paper, all the extensive approaches of heterocyclic composites, primarily thiazole derivatives, exhibit vibrant biological activity. The purpose of this work is to support methods that may be used to create various thiazole derivatives and their biological activity. This paper will offer great recommendations for potential medicine designs in the future. Full article
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6 pages, 700 KiB  
Proceeding Paper
Synthesis of Bis-Amides Employing a Plant-Derived Triterpenoid as Component in the Ugi Reaction
Chem. Proc. 2022, 12(1), 37; https://doi.org/10.3390/ecsoc-26-13560 - 14 Nov 2022
Viewed by 783
Abstract
Herein we describe the synthesis of a series of four novel triterpenoid-derived bis-amides, employing masticadienonic acid from Pistacia mexicana as a carboxylic acid component in the Ugi reaction. Products were obtained via a facile and efficient one-pot procedure under mild green conditions, [...] Read more.
Herein we describe the synthesis of a series of four novel triterpenoid-derived bis-amides, employing masticadienonic acid from Pistacia mexicana as a carboxylic acid component in the Ugi reaction. Products were obtained via a facile and efficient one-pot procedure under mild green conditions, with moderate yields (29–58%). The stereo-electronic nature of the aldehyde component influenced the reaction yields. Full article
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8 pages, 2769 KiB  
Proceeding Paper
Catalytic Cycloaddition of Diazo Compounds Based on Pharmacologically Significant and Natural Compounds to C60-Fullerene
Chem. Proc. 2022, 12(1), 38; https://doi.org/10.3390/ecsoc-26-13534 - 14 Nov 2022
Viewed by 828
Abstract
The data obtained by the authors in the field of carbon cluster chemistry, namely, the catalytic cycloaddition of diazo compounds of modern pharmacologically significant and natural compounds to C60-fullerene under the action of complex Pd–catalysts, are summarized. Cycloaddition reactions of diazoacetates, [...] Read more.
The data obtained by the authors in the field of carbon cluster chemistry, namely, the catalytic cycloaddition of diazo compounds of modern pharmacologically significant and natural compounds to C60-fullerene under the action of complex Pd–catalysts, are summarized. Cycloaddition reactions of diazoacetates, diazoamides, and diazoketones with C60-fullerene, catalyzed by Pd(acac)2–PPh3–Et3Al, with the selective formation of methano– and pyrazolinofullerenes, are new and promising classes of biologically active derivatives of C60-fullerenes. Full article
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4 pages, 386 KiB  
Proceeding Paper
Phosphorylation of Hyaluronic Acid
Chem. Proc. 2022, 12(1), 39; https://doi.org/10.3390/ecsoc-26-13535 - 14 Nov 2022
Cited by 1 | Viewed by 831
Abstract
Chemical phosphorylation of hyaluronic acid (HA) remains an unresolved problem for the chemistry of this unique polysaccharide, since convenient phosphorylating reagents are not reactive enough to obtain HA phosphates (HA-P) with a satisfactory degree of esterification of hydroxyl groups. The synthesis of phosphates [...] Read more.
Chemical phosphorylation of hyaluronic acid (HA) remains an unresolved problem for the chemistry of this unique polysaccharide, since convenient phosphorylating reagents are not reactive enough to obtain HA phosphates (HA-P) with a satisfactory degree of esterification of hydroxyl groups. The synthesis of phosphates of low-molecular-weight (43 kDa) and high-molecular-weight (0.5–0.7 MDa) HA was undertaken using such reagents as sodium trimetaphosphate Na3P3O9, H3PO4, NaH2PO4/Na2HPO4, and anhydride P2O5. Solid-phase HA esterification with P2O5 was found to be the most convenient and efficient method. The HA-P samples were characterized by XRF and NMR spectroscopy (31P and 1H-31P) and contained, depending on the HA/P2O5 ratio, 0.30–6.25% P wt., in the form of disubstituted mono-, di-, and polyphosphates. Full article
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6 pages, 788 KiB  
Proceeding Paper
Benzyl Carbamates of 4-Aminosalicylanilides as Possible BACE1 Modulators
Chem. Proc. 2022, 12(1), 40; https://doi.org/10.3390/ecsoc-26-13680 - 17 Nov 2022
Viewed by 708
Abstract
Recently, a series of thirty-eight 4-{[(benzyloxy)carbonyl]amino}-2-hydroxybenzoic acid amides designed as potential acetyl- and butyrylcholinesterase (AChE/BChE) inhibitors were described as potential drugs to alleviate the symptoms of Alzheimer’s disease (AD). Some of these compounds have shown promise for inhibiting either AChE or BChE. Since [...] Read more.
Recently, a series of thirty-eight 4-{[(benzyloxy)carbonyl]amino}-2-hydroxybenzoic acid amides designed as potential acetyl- and butyrylcholinesterase (AChE/BChE) inhibitors were described as potential drugs to alleviate the symptoms of Alzheimer’s disease (AD). Some of these compounds have shown promise for inhibiting either AChE or BChE. Since these compounds are structurally similar to agents inhibiting beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), the aim of the contribution was to verify how our compounds were able to affect this enzyme, which, when inhibited, blocks the formation of amyloid-β, but whose inhibition is associated with significant adverse effects in humans. At a concentration of 10 µM, only benzyl {4-[(4-fluorophenyl)carbamoyl]-3-hydroxyphenyl}carbamate was found to show approximately 28% inhibition of BACE1 activity. Full article
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8 pages, 1188 KiB  
Proceeding Paper
The Antiviral Activity of Trifluoromethylthiolane Derivatives
Chem. Proc. 2022, 12(1), 41; https://doi.org/10.3390/ecsoc-26-13643 - 16 Nov 2022
Viewed by 778
Abstract
The search for new antiviral agents is an important task today. The aim of this study was to elucidate the impact of trifluoromethylthiolane derivatives on herpetic and adenoviral infections. It was found that the 2-hydroxy-2-trifluoromethylthiolane significantly inhibited Herpes simplex virus type 1 (HSV-1) [...] Read more.
The search for new antiviral agents is an important task today. The aim of this study was to elucidate the impact of trifluoromethylthiolane derivatives on herpetic and adenoviral infections. It was found that the 2-hydroxy-2-trifluoromethylthiolane significantly inhibited Herpes simplex virus type 1 (HSV-1) reproduction, reducing the virus titer obtained de novo. Such activity indicates that virus offspring are formed, but the virus particles are not complete and are not able to cause an infection process. Therefore, trifluoromethylthiolane derivatives may be a potential compounds for the development on their basis agents for the treatment of herpetic infections. Full article
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5 pages, 1370 KiB  
Proceeding Paper
Ti-Catalyzed Reaction of β-Pinene with BF3·THF
Chem. Proc. 2022, 12(1), 42; https://doi.org/10.3390/ecsoc-26-13529 - 14 Nov 2022
Cited by 1 | Viewed by 744
Abstract
The reaction between β-pinene and BF3·THF in the presence of the catalytic system Cp2TiCl2/Mg was carried out for the first time to obtain a 1-fluoro-substituted boraspirane, undescribed previously. The reaction proceeds stereoselectively, but is complicated by the [...] Read more.
The reaction between β-pinene and BF3·THF in the presence of the catalytic system Cp2TiCl2/Mg was carried out for the first time to obtain a 1-fluoro-substituted boraspirane, undescribed previously. The reaction proceeds stereoselectively, but is complicated by the rearrangement of the β-pinene under the Ti-catalyzed reaction conditions. Full article
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9 pages, 611 KiB  
Proceeding Paper
Synthesis and Evaluation of Biological Activities of Schiff Base Derivatives of 4-Aminoantipyrine and Cinnamaldehydes
Chem. Proc. 2022, 12(1), 43; https://doi.org/10.3390/ecsoc-26-13684 - 17 Nov 2022
Cited by 1 | Viewed by 1724
Abstract
Schiff bases have been important compounds ever since their discovery and are both found in nature and synthesized in the laboratory. They participate in a variety of synthetic processes and possess desirable biological activity, including antibacterial, anti-inflammatory, antioxidant, and anticancer activity, among others. [...] Read more.
Schiff bases have been important compounds ever since their discovery and are both found in nature and synthesized in the laboratory. They participate in a variety of synthetic processes and possess desirable biological activity, including antibacterial, anti-inflammatory, antioxidant, and anticancer activity, among others. In this study, eight Schiff bases derived from the reaction of 4-aminoantipyrine with various cinnamaldehydes have been synthesized and characterized. All derivatives were tested in vitro on several human carcinoma cell lines to determine their antitumor activity and against different bacteria strains of clinical and food industry importance to evaluate their antibacterial activity. Several of the Schiff bases evaluated inhibited tumor cell growth in a dose-dependent manner. The compound that exhibited the most activity against all cell lines had IC50 values of less than 18 μM. On the other hand, during the evaluation of the antibacterial activity, only two Schiff base derivatives showed interesting antibacterial effects, with MIC values under 250 μM. These two Schiff base derivatives mainly exhibited a bacteriostatic effect against most of the studied bacterial strains. It is interesting to note that the same Schiff base presents the best activity in both biological evaluations. Full article
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5 pages, 1274 KiB  
Proceeding Paper
Designing a Phosphino-Thiosemicarbazone Ligand Capable of Stabilizing Coinage Metal Ions
Chem. Proc. 2022, 12(1), 44; https://doi.org/10.3390/ecsoc-26-13638 - 16 Nov 2022
Viewed by 643
Abstract
Thiosemicarbazones are interesting organic skeletons due to their great coordinative versatility and their interesting biological and pharmacological properties, as well as their structural diversity. However, the isolation of their monovalent coinage metal complexes, such as Cu(I), Ag(I) and Au(I), is a partially studied [...] Read more.
Thiosemicarbazones are interesting organic skeletons due to their great coordinative versatility and their interesting biological and pharmacological properties, as well as their structural diversity. However, the isolation of their monovalent coinage metal complexes, such as Cu(I), Ag(I) and Au(I), is a partially studied field, since co-ligands with soft donor atoms such as phosphines are required. In this context, our research group has been studying a new family of ligands capable of stabilizing coinage complexes without the need for auxiliary co-ligands. To this end, it was decided to incorporate a phosphorus atom into the structure of a thiosemicarbazone kernel. This work presents the design, synthesis and structural characterization of a new phosphino-thiosemicarbazone ligand. Full article
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5 pages, 383 KiB  
Proceeding Paper
A New Hybrid Molecule Based on (5Z,9Z)-icosa-5,9-dienoic Acid and Monocarbonyl Derivatives of Curcuminoids
Chem. Proc. 2022, 12(1), 45; https://doi.org/10.3390/ecsoc-26-13636 - 16 Nov 2022
Viewed by 614
Abstract
Efficient methods for the synthesis of previously undescribed hybrid compounds based on monocarbonyl derivatives of curcumin and 5Z,9Z-dienoic acid with yields of 58–66% are presented. The key monomer, (5Z,9Z)-icosa-5,9-dienoic acid, was prepared using the stereoselective [...] Read more.
Efficient methods for the synthesis of previously undescribed hybrid compounds based on monocarbonyl derivatives of curcumin and 5Z,9Z-dienoic acid with yields of 58–66% are presented. The key monomer, (5Z,9Z)-icosa-5,9-dienoic acid, was prepared using the stereoselective cross-cyclomagnesiation reaction of aliphatic and oxygen-containing 1,2-dienes catalyzed by Cp2TiCl2. Full article
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9 pages, 574 KiB  
Proceeding Paper
Synthesis, Insecticidal Activity and Computational Studies of Eugenol-Based Insecticides
Chem. Proc. 2022, 12(1), 46; https://doi.org/10.3390/ecsoc-26-13649 - 16 Nov 2022
Viewed by 921
Abstract
Eugenol, a natural phenolic allyl benzene that has been used as an active lead compound showing significant biological activities, including insecticidal effects on a wide variety of domestic arthropod pests, was used as the main reagent in the present work. Ester eugenol derivatives [...] Read more.
Eugenol, a natural phenolic allyl benzene that has been used as an active lead compound showing significant biological activities, including insecticidal effects on a wide variety of domestic arthropod pests, was used as the main reagent in the present work. Ester eugenol derivatives were synthesized and evaluated for their insecticidal activities against the Spodoptera frugiperda cell line. Studies of structure-based inverted virtual screening were carried out in order to identify the potential targets associated with the obtained insecticidal activity. The results indicate that the insecticide activity observed is most likely a result of the interaction of these molecules with the odorant-binding proteins and/or with acetylcholinesterase. Full article
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5 pages, 1335 KiB  
Proceeding Paper
Approach to the Synthesis of Five-Membered Organophosphorus Compounds via Alumoles and Alumolanes
Chem. Proc. 2022, 12(1), 47; https://doi.org/10.3390/ecsoc-26-13637 - 16 Nov 2022
Viewed by 689
Abstract
This work summarizes the results of a new approach to the synthesis of previously undescribed, hard-to-obtain five-membered cyclic organophosphorus compounds: 3-alkyl(aryl)-substituted phospholanes, α,ω-bisphospholanes, polycyclic phospholanes, 4,5-dialkyl(diaryl)-disubstituted 2,3-dihydrophospholes, as well as their oxides and sulfides. Alumoles and alumolanes synthesized by the reaction of cycloalumination [...] Read more.
This work summarizes the results of a new approach to the synthesis of previously undescribed, hard-to-obtain five-membered cyclic organophosphorus compounds: 3-alkyl(aryl)-substituted phospholanes, α,ω-bisphospholanes, polycyclic phospholanes, 4,5-dialkyl(diaryl)-disubstituted 2,3-dihydrophospholes, as well as their oxides and sulfides. Alumoles and alumolanes synthesized by the reaction of cycloalumination of available unsaturated compounds (terminal alkenes, α,ω-alkadienes, norbornene derivatives, symmetrical internal alkynes) with Et3Al in the presence of a Cp2ZrCl2 catalyst were used as precursors. The substitution of aluminum atoms in cyclic organoaluminum compounds for phosphorus atoms takes place using alkyl(aryl)phosphorus (III) dichlorides. The developed one-pot method gives high yields of products under mild conditions. Full article
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6 pages, 979 KiB  
Proceeding Paper
A Facile Method for Assessing the Change in Detonation Properties during Chemical Functionalization: The Case of NH2→NHNO2 and NH2→=N+=N Conversions
Chem. Proc. 2022, 12(1), 48; https://doi.org/10.3390/ecsoc-26-13566 - 14 Nov 2022
Viewed by 748
Abstract
A simple and fast procedure for estimation of the effect of chemical functionalization on the change in detonation properties of energetic materials is reported. The procedure consists of two levels. Computations at Level 1 can be performed with a pocket calculator. At Level [...] Read more.
A simple and fast procedure for estimation of the effect of chemical functionalization on the change in detonation properties of energetic materials is reported. The procedure consists of two levels. Computations at Level 1 can be performed with a pocket calculator. At Level 2, quantum-chemical calculations are needed, but these include only three computational tasks: vacuum-isolated molecule relaxation (PBE/DND) → crystal structure prediction (COMPASSII) → crystal cell relaxation (PBE/DND). Thus, we have analyzed transformation of both aromatic and aliphatic amines into the corresponding nitramines and diazo compounds. The calculations at Level 1 indicated that both crystal density (dc) and solid-state enthalpy of formation (ΔHf) are always positive and increase detonation properties, while the calculations at Level 2 revealed the amines that are the most sensitive to such chemical transformation. Full article
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6 pages, 1269 KiB  
Proceeding Paper
Cyclic 1H-Phospolane Oxides as a Potential Candidate for Cancer Therapy
Chem. Proc. 2022, 12(1), 49; https://doi.org/10.3390/ecsoc-26-13713 - 18 Nov 2022
Viewed by 1014
Abstract
Organophosphorus compounds have been investigated for agricultural and medicinal applications for decades, and a considerable number of phosphorus-containing drugs have achieved commercial success. A recent review by P. Finkbeiner et al. has shown that phosphine oxides and related phosphorus-containing functional groups are valuable [...] Read more.
Organophosphorus compounds have been investigated for agricultural and medicinal applications for decades, and a considerable number of phosphorus-containing drugs have achieved commercial success. A recent review by P. Finkbeiner et al. has shown that phosphine oxides and related phosphorus-containing functional groups are valuable polar structural elements and that they deserve to be considered as a routine part of every medicinal chemist’s toolbox. A new approach to the synthesis of previously hard-to-obtain 3-alkyl-1H-phospholanes oxides was developed by us. In order to assess the potential of five-membered cyclic organophosphorus compounds in cancer therapy, we carried out docking 3-buthyl-1H-phospholanes oxide and 2,3-dihydrophosphole in the binding site of 24 human proteins involved in oncogenesis processes. Proteins were selected using the PharmMapper in-house pharmacophore model database. The results are presented in the article. Full article
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17 pages, 10252 KiB  
Proceeding Paper
Graphitic Carbon Nitride-Supported L-Arginine: Synthesis, Charachterization, and Catalytic Activity in Multi-Component Reactions
Chem. Proc. 2022, 12(1), 50; https://doi.org/10.3390/ecsoc-26-13708 - 18 Nov 2022
Cited by 2 | Viewed by 1374
Abstract
Graphitic carbon nitride-supported L-arginine (g-C3N4@L-arginine) has been prepared as a heterogeneous catalyst for synthesizing heterocyclic compounds such as pyranopyrazole and acridinedione derivatives. High efficiency, short reaction time, and easy separation are significant features that are reasons for using g-C [...] Read more.
Graphitic carbon nitride-supported L-arginine (g-C3N4@L-arginine) has been prepared as a heterogeneous catalyst for synthesizing heterocyclic compounds such as pyranopyrazole and acridinedione derivatives. High efficiency, short reaction time, and easy separation are significant features that are reasons for using g-C3N4@L-arginine as a catalyst in one-pot multicomponent reactions. Synthesized nanocatalyst was detected by numerous analyses, such as FE-SEM (Field Emission Scanning Electron Microscopy), EDX (Energy Dispersive X-ray spectroscopy), XRD (X-Ray Diffraction analysis), TGA (Thermo Gravimetric Analysis), and FT-IR (Fourier Transform Infrared Spectroscopy). G-C3N4@L-arginine nanocatalyst was reused 5 times in the reaction with no apparent decrease in reaction yield, which shows acceptable recyclability. Full article
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8 pages, 1039 KiB  
Proceeding Paper
Can the Antimicrobial Peptide Ctx(Ile21)-Ha-Ahx-Cys Grafted onto Nanochitosan Sensitize Extensively Drug-Resistant Mycobacterium tuberculosis?
Chem. Proc. 2022, 12(1), 51; https://doi.org/10.3390/ecsoc-26-13700 - 18 Nov 2022
Viewed by 1192
Abstract
The infectious agent Mycobacterium tuberculosis (MTB) has several defense and resistance mechanisms that must be eliminated. The treatment is prolonged, which in many cases generates susceptibility to microbial resistance. This research aimed to study whether the antimicrobial peptide Ctx(Ile21)-Ha-Ahx-Cys (Ctx-SH) functionalized [...] Read more.
The infectious agent Mycobacterium tuberculosis (MTB) has several defense and resistance mechanisms that must be eliminated. The treatment is prolonged, which in many cases generates susceptibility to microbial resistance. This research aimed to study whether the antimicrobial peptide Ctx(Ile21)-Ha-Ahx-Cys (Ctx-SH) functionalized in nanochitosan matrices could eliminate resistant MTB. For this, a nanosystem was developed with chitosan matrices previously modified with N-acetylcysteine functionalized to Ctx-SH. Modified chitosan nanoparticles (NPQ) were obtained by ionic gelation using sodium tripolyphosphate and loaded with rifampicin. Both chitosan and NPQ modifications were analyzed for physicochemical parameters by Fourier/Raman transform infrared spectroscopy and Zeta potential. Antimicrobial activity was performed in a level 3 biosafety laboratory with strains H37Rv (standard) and CF169 (extensively drug-resistant, XDR) incubated in 7H9 broth supplemented with oleic acid, albumin, dextrose, and catalase at 37 °C and 5% CO2 and read using fluorescence with 0.01% resazurin after 7 days. Insertion and mapping of NPQ into macrophages were assessed using a confocal microscope after 24 h with NPQ conjugated to fluorescein isothiocyanate. Preliminary results show that the spectroscopies corroborate the hypothesis of the functionalization of the Ctx-SH peptide to the chitosan-N-acetylcysteine system because, when comparing the three spectroscopies, a gradual increase in the intensity of several bands and the formation of captive disulfide are observed, and the Zeta potential (+30 mV) confirmed high application stability. Bacterial inhibition studies revealed that rifampicin-loaded antimicrobial peptide-conjugated chitosan nanoparticles have better activity than rifampicin alone against CF169, with a minimum inhibitory concentration of <0.977 µg/mL, similar to the standard strain. In addition, it was shown that NPQ would be able to enter the macrophage without causing toxicity and thus take better advantage of the activity of rifampicin. Finally, it is possible to verify that the nanobioconjugation of the Ctx-SH-N-acetylcysteine-chitosan compound is capable of enhancing the activity of obsolete drugs and/or sensitizing XDR bacteria. Full article
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5 pages, 1116 KiB  
Proceeding Paper
Synthesis and X-ray Diffraction of Cyclopalladated Compounds Derived from Imine Ligands
Chem. Proc. 2022, 12(1), 52; https://doi.org/10.3390/ecsoc-26-13699 - 18 Nov 2022
Viewed by 971
Abstract
The crystal structures of mononuclear cyclopalladated compounds with phosphine ligands are investigated. The reactions of the five-membered cyclopalladated dinuclear complexes [Pd(L)(µ-Cl)]2 with the monophosphine ligand (PPh3) and diphosphine ligand (dppm) in the molar ratio of 1:2, and ammonium hexafluoride in [...] Read more.
The crystal structures of mononuclear cyclopalladated compounds with phosphine ligands are investigated. The reactions of the five-membered cyclopalladated dinuclear complexes [Pd(L)(µ-Cl)]2 with the monophosphine ligand (PPh3) and diphosphine ligand (dppm) in the molar ratio of 1:2, and ammonium hexafluoride in the case of compound b, result in the mononuclear complexes [Pd{2,3,4-(CHO)C6H3C(H)=NCy}{PPh3}[Cl] (1a) and [Pd{2,3,4-(CHO)C6H3C(H)=NCy}{Ph2PCH2PPh2-P,P}][PF6] (1b). Full article
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8 pages, 2993 KiB  
Proceeding Paper
Peculiarities of Obtaining and Modeling the Structure of Nimesulide Clathrate Complexes with β- and γ-Cyclodextrins
Chem. Proc. 2022, 12(1), 53; https://doi.org/10.3390/ecsoc-26-13707 - 18 Nov 2022
Cited by 1 | Viewed by 1022
Abstract
This work investigates the inclusion of the nimesulide molecule into the beta- and gamma- cyclodextrin cavity and explores the application of molecular modelling for the purposes of proving the host-guest complexation process. The author’s experimental method is based upon the basic methods of [...] Read more.
This work investigates the inclusion of the nimesulide molecule into the beta- and gamma- cyclodextrin cavity and explores the application of molecular modelling for the purposes of proving the host-guest complexation process. The author’s experimental method is based upon the basic methods of obtaining inclusion complexes. A combination of physical and chemical methods was utilized in order to analyze the compounds obtained qualitatively and quantitatively. In addition, it was decided that the focus will be on figuring out the possibility applying computer modeling. The characteristics of the molecular systems under study were calculated using the «Gaussian 09W» software package (Revision version 16 A.03). The functionality of this software package allowed us to apply both the restricted Hartree–Fock (RHF) method, and the hybrid density functional method-B3LYP. The 6–31 G split-valence basis set was utilized for all subsequent calculations, to quantify the influence of the additional polarization and diffuse functions on the calculations. Using computational chemistry, the structures of γ-, β-cyclodextrin, nimesulide, and surface complex compounds were constructed and optimized. The possible structures of nimesulide inclusion complexes with β-, γ-cyclodextrin were also designed. The results obtained will influence the evaluation of the possibility of obtaining the clathrate complex. The crystal structure of the nimesulide inclusion complex obtained by us with γ-cyclodextrin was experimentally confirmed by X-ray diffraction analysis. To date, not many works are known to utilize these molecular modeling techniques in the field of supramolecular chemistry based on an independently synthesized inclusion complex. Full article
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6 pages, 1605 KiB  
Proceeding Paper
Medicinal Traits of the Phenolic Compound from Foeniculum vulgare for Oligomenorrhea
Chem. Proc. 2022, 12(1), 54; https://doi.org/10.3390/ecsoc-26-13724 - 21 Nov 2022
Viewed by 2109
Abstract
A phenolic compound in Foeniculum vulgare can improve human health. Foeniculum vulgar contains flavonoids, glycosides, and other constituents that are used for medicinal ailments. Trans-anethole, fenchone, and estragole essential oils are the main ingredients in F. vulgare seeds. The principle component of fennel [...] Read more.
A phenolic compound in Foeniculum vulgare can improve human health. Foeniculum vulgar contains flavonoids, glycosides, and other constituents that are used for medicinal ailments. Trans-anethole, fenchone, and estragole essential oils are the main ingredients in F. vulgare seeds. The principle component of fennel oil, anethole, has structural similarity with the synthetic oestrogen diethylstilbestrol, making it an active estrogenic agent. Women with PCOS may exhibit obesity, amenorrhea, oligomenorrhea, infertility, or androgenic features, which are characterized by the absence of ovulation and hyperandrogenism. Oligomenorrhea is a kind of irregular menstruation period. Treatment of oligomenorrhea depends on the causes; the main cause of oligomenorrhea is the presence of polycystic ovarian syndrome (PCOS), with 75–85%experiencing infrequent periods. This mini-review focuses on F. vulgare seeds as an advantageous addition to treat PCOS. Women with PCOS also have a lower level of the hormone progesterone due to the absence or reduction in ovulation. Numerous phytoestrogens can be found in F.vulgare seeds; with less insulin resistance and lower blood sugar level, fennel phytoestrogen content is beneficial. It is also thought to aid in reducing the cellularim balance that causes PCOS’s metabolic abnormalities. Full article
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7 pages, 558 KiB  
Proceeding Paper
Nematicidal Activity of Oxygen-Containing Aliphatic Compounds on Bursaphelenchus xylophilus, B. mucronatus and B. fraudulentus 
Chem. Proc. 2022, 12(1), 55; https://doi.org/10.3390/ecsoc-26-13536 - 14 Nov 2022
Viewed by 1186
Abstract
The pinewood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of pine-wilt disease (PWD), is a threat to Pinus forests in Asia and Europe. Bursaphelenchus mucronatus and B. fraudulentus are closely related non-pathogenic pine-wood nematodes. In the present work, four medium-chain aliphatic alcohols [...] Read more.
The pinewood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of pine-wilt disease (PWD), is a threat to Pinus forests in Asia and Europe. Bursaphelenchus mucronatus and B. fraudulentus are closely related non-pathogenic pine-wood nematodes. In the present work, four medium-chain aliphatic alcohols (C10 to C13) were evaluated in direct-contact bioassays against B. xylophilus, B. mucronatus and B. fraudulentus. The compounds showed high nematicidal activity against the species tested. The lowest values for half-maximal effective concentrations (EC50) were determined in B. xylophilus and B. fraudulentus, suggesting a higher sensibility to these compounds. Further bioassays will include compounds with different chain lengths and functional groups to explore the diversity in the activity of oxygen-containing aliphatic compounds for a more targeted sustainable-control strategy for the PWN. Full article
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7 pages, 1539 KiB  
Proceeding Paper
New 2,6-Bis(5-phenyloxazolyl)pyridine Ligands for Luminescent LnIII Complexes
Chem. Proc. 2022, 12(1), 56; https://doi.org/10.3390/ecsoc-26-13714 - 18 Nov 2022
Viewed by 1023
Abstract
Lanthanide (Ln(III)) luminescent complexes have been attracting interest for technological applications and molecular imaging. The luminescence of Ln(III)) ions is weak and depends on the use of light absorbing coordination ligands which sensitizes the lanthanide ion. A large variety of coordination ligands has [...] Read more.
Lanthanide (Ln(III)) luminescent complexes have been attracting interest for technological applications and molecular imaging. The luminescence of Ln(III)) ions is weak and depends on the use of light absorbing coordination ligands which sensitizes the lanthanide ion. A large variety of coordination ligands has been screened such as dipicolinates, oligo-pyridines, cyclen and crown ether derivatives, porphyrins, cryptands or calixarenes. In our research group we have developed an expeditious methodology to prepare bis(oxazolyl)pyridine ligands for LnIII from threonine and 2,6-pyridinedicarbonyl dichloride. In this work, two new pyridine-bis-oxazolyl ligands with an aromatic ring in position 5 of the oxazole ring were prepared from phenyl-serine and 2,6-pyridinedicarbonyl dichloride. The photophysical properties of compounds 1 and 2 were studied in acetonitrile and in Tris-HCl buffer (0.1 M, pH 7.1). These compounds were used for complexation with Eu(III) and/or Tb(III) ions and the photophysical properties of the complexes studied. Luminescence titrations with anhydrous EuCl3 and TbCl3 allowed the determination of the stoichiometry of the complexes and of the stability constants. Full article
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5 pages, 2017 KiB  
Proceeding Paper
Oxidation Processes in a Phosphine-Thiocarbohydrazone Ligand
Chem. Proc. 2022, 12(1), 57; https://doi.org/10.3390/ecsoc-26-13559 - 14 Nov 2022
Viewed by 592
Abstract
In this work, we isolated a pentadentate [P2N2S] phosphine-thiocarbohydrazone ligand H2L with a bulky phosphine group in both linker domains that undergoes an oxidation process in solution. This ligand was synthesized by a direct reaction between two [...] Read more.
In this work, we isolated a pentadentate [P2N2S] phosphine-thiocarbohydrazone ligand H2L with a bulky phosphine group in both linker domains that undergoes an oxidation process in solution. This ligand was synthesized by a direct reaction between two equivalents of 2-diphe-nylphosphinebenzaldehyde and one equivalent of thiocarbohydrazide. Two types of crystals de-rived from this ligand were obtained and studied using X-ray diffraction spectroscopy. One structure corresponds to the monooxidized ligand H2L(O) while the other indicates a dioxidation of the compound, H2L(OO). Full article
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9 pages, 1506 KiB  
Proceeding Paper
Synthesis of 6-(4-Chlorophenyl)-N-aryl-4-(trichloromethyl)-4H-1,3,5-oxadiazin-2-amines: A Comparative Evaluation of Dehydrosulfurization Methods of Starting 4-Chloro-N-(2,2,2 -trichloro-1-(3-arylthioureido)ethyl)benzamides
Chem. Proc. 2022, 12(1), 58; https://doi.org/10.3390/ecsoc-26-13538 - 14 Nov 2022
Cited by 1 | Viewed by 809
Abstract
Derivatives of 1,3,5-oxadiazine are of interest to pharmacy, medicine, and agriculture as potential biologically active substances. These compounds have found wide application in organic synthesis and supramolecular chemistry. In this paper, we discuss and compare the effectiveness of two approaches to the dehydrosulfurization [...] Read more.
Derivatives of 1,3,5-oxadiazine are of interest to pharmacy, medicine, and agriculture as potential biologically active substances. These compounds have found wide application in organic synthesis and supramolecular chemistry. In this paper, we discuss and compare the effectiveness of two approaches to the dehydrosulfurization of 4-chloro-N-(2,2,2-trichloro-1-(3-arylthioureido)ethyl)benzamides resulting in the formation of 6-(4-chlorophenyl)-N-aryl-4-(trichloromethyl)-4H-1,3,5-oxadiazin-2-amines. Dicyclohexylcarbodiimide (DCC) or a mixture of iodine with triethylamine was used as a dehydrosulfurizing agent. It is shown that, in the case of using DCC, the target products are predominantly formed in high yields. However, the use of the I2 + Et3N mixture made it possible to obtain several new compounds of this class, which could not be obtained under the DCC action. The structure of all new compounds was confirmed by 1H and 13C NMR spectroscopy data. Full article
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3 pages, 191 KiB  
Proceeding Paper
Extraction of Sodium Alginate from Charophyceae Algae
Chem. Proc. 2022, 12(1), 59; https://doi.org/10.3390/ecsoc-26-13639 - 16 Nov 2022
Viewed by 646
Abstract
This study examined the rheological properties of alginates, one of the main products obtained from algae. These polysaccharides are widely used in fields such as pharmaceuticals, medical technology, cosmetics, food, agriculture and the textile and paper industries. Therefore, sodium alginate was obtained from [...] Read more.
This study examined the rheological properties of alginates, one of the main products obtained from algae. These polysaccharides are widely used in fields such as pharmaceuticals, medical technology, cosmetics, food, agriculture and the textile and paper industries. Therefore, sodium alginate was obtained from waterweed (Charophyceae) in the following experiment. The structure and composition of the sodium alginate were analyzed using physical and chemical research methods: IR spectroscopy and XRD. Full article
9 pages, 2591 KiB  
Proceeding Paper
Cyclodextrin-Based Host–Guest Supramolecular Nanofibrous Composite for Biomedical Applications
Chem. Proc. 2022, 12(1), 60; https://doi.org/10.3390/ecsoc-26-13523 - 14 Nov 2022
Viewed by 862
Abstract
Cyclodextrins (CDs) are macrocyclic oligosaccharides, containing between six and eight alpha(1 → 4)-linked glucopyranoses. CDs have a hydrophobic cone-shaped internal cavity and a hydrophilic exterior surface. They form non-covalent inclusion complexes (ICs) with various drugs by trapping the full or partial inclusions in [...] Read more.
Cyclodextrins (CDs) are macrocyclic oligosaccharides, containing between six and eight alpha(1 → 4)-linked glucopyranoses. CDs have a hydrophobic cone-shaped internal cavity and a hydrophilic exterior surface. They form non-covalent inclusion complexes (ICs) with various drugs by trapping the full or partial inclusions in their cavity. Supramolecular ICs have gained attention in engineering entrapped drug performance field due to their potential to protect and modify the physicochemical properties of entrapped lipophilic and volatile drugs. However, the poor structural and mechanical properties of pure CD-ICs could restrict their application and the need for a suitable carrier system. Electrospun nanofibers have been the center of attention for biomedical applications due to their tunable physicochemical properties. Recent studies have highlighted that the entrapment of drug/CD-based ICs into nanofibers is an active research area since it facilitates high encapsulation, it modulates the release profile of the guest, integrates multi-type drugs, and leads to a synergistic effect. This mini-review first summarizes the potential benefits and shortcomings of drug/CD-ICs and nanofibers, and then, we discuss the advancements in the fabrication and characteristics of CD-ICs embedded nanofibers, along with some practical suggestions for potential biomedical applications. Full article
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5 pages, 736 KiB  
Proceeding Paper
Synthesis of 1,3-Diyne Derivatives of Lembehyne B with Antitumor and Neuritogenic Activity
Chem. Proc. 2022, 12(1), 61; https://doi.org/10.3390/ecsoc-26-13525 - 14 Nov 2022
Viewed by 765
Abstract
The report presents data from our studies on obtaining lembehyne B derivatives with cytotoxic and neuritogenic activity. The methods and approaches to the synthesis of the above-mentioned lembehynes presented in the report are based on the use of the catalytic cross-cyclomagnesiation of 1,2-dienes [...] Read more.
The report presents data from our studies on obtaining lembehyne B derivatives with cytotoxic and neuritogenic activity. The methods and approaches to the synthesis of the above-mentioned lembehynes presented in the report are based on the use of the catalytic cross-cyclomagnesiation of 1,2-dienes (the Dzhemilev reaction) at the key stage of the synthesis. Full article
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5 pages, 655 KiB  
Proceeding Paper
New Caffeine Derivatives as Multitarget Agents for the Therapy of Alzheimer’s Disease
Chem. Proc. 2022, 12(1), 62; https://doi.org/10.3390/ecsoc-26-13578 - 14 Nov 2022
Viewed by 820
Abstract
In this work we present the microwave-assisted synthesis and in vitro acetylcholinesterase inhibition of a series of new caffeine derivatives. The design of these new compounds was inspired by the caffeine–pyrrolidine hybrids that act as AChE inhibitors and nAChR activators, previously reported by [...] Read more.
In this work we present the microwave-assisted synthesis and in vitro acetylcholinesterase inhibition of a series of new caffeine derivatives. The design of these new compounds was inspired by the caffeine–pyrrolidine hybrids that act as AChE inhibitors and nAChR activators, previously reported by our group. All of the new caffeine analogs inhibited AChE. Among them, the compound 2b (1,3-dimethyl-7-(6-(piperidin-1-yl)hexyl)-3,7-dihydro-1H-purine-2,6-dione) showed the strongest effect (IC50 = 0.17 µM) on AChE, with higher potency than caffeine–pyrrolidine hybrids. These preliminary studies suggest that these new compounds might be interesting multifunctional drugs destined to stimulate cholinergic signage. Full article
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4 pages, 1078 KiB  
Proceeding Paper
Fe-Catalyzed Synthesis of 2-Benzoxazolone—An Important Fragment of Biologically Active Compounds
Chem. Proc. 2022, 12(1), 63; https://doi.org/10.3390/ecsoc-26-13564 - 14 Nov 2022
Viewed by 698
Abstract
2-Benzoxazolone, as well as its derivatives, are valuable structural fragments of a number of important biologically active substances. 2-Benzoxazolone derivatives are promising as antitumor, antimicrobial, antiretroviral, anticonvulsant, tranquilizing, and insecticidal agents. 2-Benzoxazolone is usually produced by the condensation of o-aminophenol with urea, phosgene, [...] Read more.
2-Benzoxazolone, as well as its derivatives, are valuable structural fragments of a number of important biologically active substances. 2-Benzoxazolone derivatives are promising as antitumor, antimicrobial, antiretroviral, anticonvulsant, tranquilizing, and insecticidal agents. 2-Benzoxazolone is usually produced by the condensation of o-aminophenol with urea, phosgene, and other carbonic acid derivatives. There are also methods for the synthesis of 2-benzoxazolone from salicylamide with trichloroisocyanuric acid as a chlorinating agent, from hydroxybenzoic acid using ammonium azide and the Vilsmeier complex. The disadvantages of these methods are the high cost of the initial reagents, the need to use aggressive and toxic reagents (phosgene, ammonium azide), and the complexity of the hardware design for the reactors. We have developed the highly efficient oxidative cyclocarbonylation of 2-aminophenol to oxazolidin-2-one using FeCl3*6H2O and Fe(acac)3 as catalysts under relatively mild conditions (100–120 °C) in the presence of CCl4 and water. We assume that in situ-formed carbon dioxide is involved in a cyclization reaction with o-aminophenol to form the target 2-benzoxazole. The reaction takes 2–10 h to give 2-benzoxazolone a high yield. Full article
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5 pages, 1269 KiB  
Proceeding Paper
Depolymerization of Heparin Benzyl Ester in a Flow System
Chem. Proc. 2022, 12(1), 64; https://doi.org/10.3390/ecsoc-26-13718 - 18 Nov 2022
Viewed by 1257
Abstract
The preparation of enoxaparin via the base-promoted depolymerization of heparin is well known. In this paper, we present our efforts to convert this preparation into a flow method. Streams of base and ester solutions are combined and heated in a flow reactor, and [...] Read more.
The preparation of enoxaparin via the base-promoted depolymerization of heparin is well known. In this paper, we present our efforts to convert this preparation into a flow method. Streams of base and ester solutions are combined and heated in a flow reactor, and the variations in flow rate, temperature, and residence time were examined. NMR analysis demonstrated that careful control of the reaction parameters affords enoxaparin-like materials. An analysis was carried out by NMR spectroscopy and the optimum conditions were determined. Full article
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4 pages, 521 KiB  
Proceeding Paper
Cp2TiCl2—Catalyzed Synthesis of Tertiary Alcohols by the Reaction of AlCl3 with Ketones and Aryl Olefins
Chem. Proc. 2022, 12(1), 65; https://doi.org/10.3390/ecsoc-26-13706 - 18 Nov 2022
Viewed by 1159
Abstract
We have previously obtained significant results in the cycloalumination of olefins with EtAlCl2 in the presence of magnesium and a Cp2ZrCl2 or Cp2TiCl2 catalyst. Here we report the development of an efficient one-pot catalytic method for [...] Read more.
We have previously obtained significant results in the cycloalumination of olefins with EtAlCl2 in the presence of magnesium and a Cp2ZrCl2 or Cp2TiCl2 catalyst. Here we report the development of an efficient one-pot catalytic method for the synthesis of tertiary alcohols from AlCl3, aryl olefins, and ketones under the action of Cp2TiCl2. The developed method for producing tertiary alcohols has a general character and allows the conversion of styrene and substituted styrenes (ortho-, para-methylstyrenes) into aryl-substituted tertiary alcohols with yields of up to 76% in the reaction with acetone or methyl ethyl ketone. We assume that the reaction proceeds through the formation of a titanacyclopropane intermediate. Full article
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7 pages, 2558 KiB  
Proceeding Paper
New Photochemical Properties of Azidoaniline and Ciprofloxacin
Chem. Proc. 2022, 12(1), 66; https://doi.org/10.3390/ecsoc-26-13571 - 14 Nov 2022
Cited by 1 | Viewed by 737
Abstract
There is a trend to find new ways of using photocatalysis in order to synthesize valuable products or to control or track live processes with special fluorescence-based molecular probes. The paper presents some results concerning new photochemical properties of azidoaniline, its 7-nitrobenzofurazan (NBD) [...] Read more.
There is a trend to find new ways of using photocatalysis in order to synthesize valuable products or to control or track live processes with special fluorescence-based molecular probes. The paper presents some results concerning new photochemical properties of azidoaniline, its 7-nitrobenzofurazan (NBD) derivative and ciprofloxacin derivatives. Full article
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7 pages, 1817 KiB  
Proceeding Paper
Current Trends in the Synthesis of Practically Important Five-Membered Boracarbocycles by Transmetalation of Aluminacarbocycles with Boron Halides
Chem. Proc. 2022, 12(1), 67; https://doi.org/10.3390/ecsoc-26-13698 - 18 Nov 2022
Viewed by 1268
Abstract
The data obtained by the authors in the field of chemistry of substituted borolanes and 2,3-dihydro-1H-boroles are summarized. The authors developed a selective method for the synthesis of five-membered boracarbocycles via transmetalation of aluminacarbocycles, obtained by the catalytic cycloalumination of unsaturated [...] Read more.
The data obtained by the authors in the field of chemistry of substituted borolanes and 2,3-dihydro-1H-boroles are summarized. The authors developed a selective method for the synthesis of five-membered boracarbocycles via transmetalation of aluminacarbocycles, obtained by the catalytic cycloalumination of unsaturated compounds (terminal olefins or acetylenes) with AlEt3 in the presence of Cp2ZrCl2 as a catalyst by boron halides (BF3·Et2O, BCl3, and BBr3). Some examples of the use of this approach to modify steroid compounds (in particular, to introduce a borolan fragment into them) are described in this review. Full article
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5 pages, 2575 KiB  
Proceeding Paper
Chemo-Selective Protection of Aldehydes Functional Group Catalyzed by MOFs
Chem. Proc. 2022, 12(1), 68; https://doi.org/10.3390/ecsoc-26-13645 - 16 Nov 2022
Viewed by 740
Abstract
A metal-organic framework Zn2(BDC)2(DABCO) was employed as a reusable heterogeneous acidic catalyst in the acylation reaction of various benzaldehydes with acetic anhydride under microwave irradiation. The outstanding features of this efficient solvent-free method are short reaction time, ease of [...] Read more.
A metal-organic framework Zn2(BDC)2(DABCO) was employed as a reusable heterogeneous acidic catalyst in the acylation reaction of various benzaldehydes with acetic anhydride under microwave irradiation. The outstanding features of this efficient solvent-free method are short reaction time, ease of product separation, greatest yields, and the ability to reuse the catalyst several times. Full article
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7 pages, 674 KiB  
Proceeding Paper
In Silico Analysis Applied to the Study of Cytotoxicity in Natural Products
Chem. Proc. 2022, 12(1), 69; https://doi.org/10.3390/ecsoc-26-13557 - 14 Nov 2022
Cited by 2 | Viewed by 1520
Abstract
With the emergence of technological advances, computational analysis in research has become promising by enabling the emergence of scientific production without the need for an experimental laboratory, and it has therefore begun to be used in various sectors, including cytotoxicity. From this perspective, [...] Read more.
With the emergence of technological advances, computational analysis in research has become promising by enabling the emergence of scientific production without the need for an experimental laboratory, and it has therefore begun to be used in various sectors, including cytotoxicity. From this perspective, the main objective of this study is to understand the importance of computational analysis for the study of cytotoxicity in natural products in addition to understanding scientific advances on this topic. Thus, this is a narrative-type bibliographic review, carried out between March and September 2022, through the digital databases of Pubmed, SciELO, and the Virtual Health Library with the adoption of the search formula configured with the available descriptors: “in silico analysis”, “cytotoxic”, and “natural products”. This work reaffirmed the importance of computer simulations on cytotoxicity in natural products and provided verification that these types of analyses are a source of knowledge about the structures of natural products, emphasizing the use of in silico analysis of cytotoxic agents, anticancer action, and the treatment of other pathologies. With regard to effectiveness, it is clear that the software reflects results that are similar to studies carried out in vivo. It is noteworthy that the in silico method has an accentuated scientific importance as it allows for a greater adaptability and a lower cost of time and space for research. Thus, such methodology becomes essential in the process of cytotoxicity analysis, obtaining great potential in pharmacological research. Full article
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6 pages, 931 KiB  
Proceeding Paper
Ionogels: Polimeric and Sol-Gel Silica Nanoscaffolds of Ionic Liquids as Smart Materials
Chem. Proc. 2022, 12(1), 70; https://doi.org/10.3390/ecsoc-26-13686 - 17 Nov 2022
Viewed by 733
Abstract
The purpose of this work is to check the viability of mixtures of ionic liquids and lithium salt as electrolytes in Li- batteries. Firstly, the determination of the thermo-electrical properties of liquid mixtures of the ionic liquid N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide [BMPyrr][TFSI] with [Li][TFSI] salt [...] Read more.
The purpose of this work is to check the viability of mixtures of ionic liquids and lithium salt as electrolytes in Li- batteries. Firstly, the determination of the thermo-electrical properties of liquid mixtures of the ionic liquid N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide [BMPyrr][TFSI] with [Li][TFSI] salt at different concentrations was performed. Additionally, these results were compared with the corresponding ionogels of these mixtures designed by two different gelation methods, one of them using Poly (vinylidene fluoride) (PVDF) as a supporting matrix and the other one using a silica matrix. Full article
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5 pages, 395 KiB  
Proceeding Paper
Bioactive Diterpenoids Obtained from Grindelia ventanensis Bartola & Tortosa (Asteraceae)
Chem. Proc. 2022, 12(1), 71; https://doi.org/10.3390/ecsoc-26-13581 - 14 Nov 2022
Cited by 1 | Viewed by 790
Abstract
Grindelia ventanensis (Asteraceae) is an endemic species growing wild in Argentina. In this work, we studied the dichloromethane extract of this plant for their antioxidant activity and cholinesterase inhibition. This extract was fractionated using column chromatography and HPLC. Six diterpenoids were isolated and [...] Read more.
Grindelia ventanensis (Asteraceae) is an endemic species growing wild in Argentina. In this work, we studied the dichloromethane extract of this plant for their antioxidant activity and cholinesterase inhibition. This extract was fractionated using column chromatography and HPLC. Six diterpenoids were isolated and identified using RMN and MS analyses. The 13-methyl-17-oxo-labda-7,13-diene-15-oic acid elicited the best results in both bioassays, with IC50 = 11.04 µM in the AChE inhibition test and an antioxidant activity comparable to trolox, the reference antioxidant (IC50 = 7.13 µM). Significant bioactivity was also observed for the rest of the isolated compounds. Full article
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5 pages, 2475 KiB  
Proceeding Paper
Transition Metal-Catalyzed, “Ligand Free” P–C Coupling Reactions under MW Conditions
Chem. Proc. 2022, 12(1), 72; https://doi.org/10.3390/ecsoc-26-13647 - 16 Nov 2022
Viewed by 711
Abstract
A method for “P-ligand free”, Pd(OAc)2-catalyzed P–C coupling reactions under MW conditions was investigated in our group. In our latest work, this procedure was extended to dihalogenobenzenes. Copper-promoted reactions were studied experimentally and using quantum chemical calculations. Full article
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7 pages, 386 KiB  
Proceeding Paper
Synthesis, Characterization and Biological Activity of Hydrazones and Their Copper(II) Complexes
Chem. Proc. 2022, 12(1), 73; https://doi.org/10.3390/ecsoc-26-13576 - 14 Nov 2022
Viewed by 1127
Abstract
The fundamental importance of copper as a redox-active metal essential to the functioning of several metabolic enzymes provides a wide range of its biological activity pathways. Copper(II) coordination compounds are known to exhibit potent antiproliferative, antibacterial, nuclease, anti-inflammatory and antimycobacterial activities. Hydrazones are [...] Read more.
The fundamental importance of copper as a redox-active metal essential to the functioning of several metabolic enzymes provides a wide range of its biological activity pathways. Copper(II) coordination compounds are known to exhibit potent antiproliferative, antibacterial, nuclease, anti-inflammatory and antimycobacterial activities. Hydrazones are organic ligands commonly used for complexation with copper(II) that possess antibacterial, antiviral and antifungal properties. Copper–ligand interaction might facilitate charge delocalization and increase net hydrophobicity of the system, resulting in its enhanced pharmacological activity. Coordination compounds of Cu(II) with 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde derived hydrazone, nitrofurantoin and ftivazide have been synthesized, characterized by means of elemental and XRD analysis, FT-IR, UV-Vis and NMR spectroscopy and tested for antibacterial activity in vitro on Gram-positive and Gram-negative bacteria. Full article
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5 pages, 2660 KiB  
Proceeding Paper
Pb(II) Adsorption by a Calcium Metal-Organic Framework
Chem. Proc. 2022, 12(1), 74; https://doi.org/10.3390/ecsoc-26-13723 - 21 Nov 2022
Viewed by 1203
Abstract
Among the water pollution sources, heavy metals are considered the most hazardous because of their high toxicity to human health and their ability to badly damage the kidneys, brain, and nerves, as well as cause birth defects. Based on the promising features of [...] Read more.
Among the water pollution sources, heavy metals are considered the most hazardous because of their high toxicity to human health and their ability to badly damage the kidneys, brain, and nerves, as well as cause birth defects. Based on the promising features of metal-organic frameworks ( MOFs), they could act as a favorable candidate in heavy metal removal applications. A calcium-based metal-organic framework was synthesized by the deposition method using benzene-1,2,4,5-tetracarboxylate as a linker. After characterization of the MOF was performed using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) analyses, it was applied to efficient adsorption of Pb(II) pollutant ions. The potential of obtained MOF, [Ca(H2btec)·H2O]n, H2btec: benzene-1,2,4,5-tetracarboxylic acid was investigated by adsorbing Pb(II) ions in an aqueous solution, separating the adsorbent using centrifugation, and finally measuring the residual Pb(II) ions using the ICP-AES method. Full article
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4 pages, 1500 KiB  
Proceeding Paper
Antimicrobial Activity of Ba-MOF
Chem. Proc. 2022, 12(1), 75; https://doi.org/10.3390/ecsoc-26-13725 - 21 Nov 2022
Viewed by 1310
Abstract
The increasing tolerance and resistance of pathogens to conventional antibiotics is a global health issue, and there is a need to use effective and new substances. Metal–organic frameworks (MOFs) are highly functional materials with antimicrobial properties that come from their composition, structure, and [...] Read more.
The increasing tolerance and resistance of pathogens to conventional antibiotics is a global health issue, and there is a need to use effective and new substances. Metal–organic frameworks (MOFs) are highly functional materials with antimicrobial properties that come from their composition, structure, and high internal volume, which could be a source for antimicrobial guest molecules integrated into the pores. In addition, MOFs can contain more than one type of metal ion in the same structure. In this work, a metal–organic framework, [Ba(H2btec)·H2O]n, was synthesized by the deposition method using benzene-1,2,4,5-tetracarboxylic acid (H4btec) and Ba(NO3)2. Characterization of the MOF was performed using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) and x-ray fluorescence (XRF) alyses. The metal–organic framework was used against Gram-positive and Gram-negative bacteria including Keleb peneumonia, Staph coccus aureus, Staph sapropphyticus, and Esherichia coli. Full article
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7 pages, 1455 KiB  
Proceeding Paper
Pyrene-4,5,9,10-Tetrachalcogenone Derivatives: A Computational Study on Their Potential Use as Materials for Batteries
Chem. Proc. 2022, 12(1), 76; https://doi.org/10.3390/ecsoc-26-13554 - 14 Nov 2022
Viewed by 744
Abstract
Polycyclic aromatic hydrocarbons are versatile building blocks for conjugated materials and can be applied in molecular electronics. Pyrenes are known as the best organic chromophores, and pyrene itself is known as an electron donor. Likewise, quinones are promising electrode materials for lithium-ion batteries. [...] Read more.
Polycyclic aromatic hydrocarbons are versatile building blocks for conjugated materials and can be applied in molecular electronics. Pyrenes are known as the best organic chromophores, and pyrene itself is known as an electron donor. Likewise, quinones are promising electrode materials for lithium-ion batteries. The calculations were performed for pyrene-4,5,9,10-tetrathione, pyrene-4,5,9,10-tetraselenone and pyrene-4,5,9,10-tetratellurone, and the results were compared with those for pyrene-4,5,9,10-tetraone. The results obtained indicate that the sulfur derivative is a suitable candidate for further experimental studies since, although selenium and tellurium compounds present better prospects than 4,5,9,10-tetraoxopyrene, they require the improvement of available synthetic techniques or even the discovery of new ones. Full article
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4 pages, 1490 KiB  
Proceeding Paper
Antibacterial Activity of Ag2O/SrO/CaO Nanocomposite
Chem. Proc. 2022, 12(1), 77; https://doi.org/10.3390/ecsoc-26-13577 - 14 Nov 2022
Viewed by 786
Abstract
The increase in bacterial resistance to one or several antibiotics has become a global health problem. Nanocomposites have become a tool against multidrug-resistant bacteria. A nanocomposite, Ag2O/SrO/CaO, was prepared from AgNO3, SrCl2·6H2O, CaCl2, [...] Read more.
The increase in bacterial resistance to one or several antibiotics has become a global health problem. Nanocomposites have become a tool against multidrug-resistant bacteria. A nanocomposite, Ag2O/SrO/CaO, was prepared from AgNO3, SrCl2·6H2O, CaCl2, and a solution of Na2CO3 via the calcination of the salts mixture. The nanocomposite was successfully prepared by the co-precipitation method and completely according to green chemistry, in terms of synthesis method, solvent and precursors. The nanocomposite was characterized by XRD, XRF, and FESEM analyses. Afterwards, the nanocomposite was applied for antibacterial activity against gram-positive and gram-negative bacteria including PS Aeruginosa, Keleb peneumonia, Staph coccus aureus, Staph sapropphyticus, and Escherichia coli. Full article
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15 pages, 7821 KiB  
Proceeding Paper
Designing and In Silico Evaluation of Some Non-Nucleoside MbtA Inhibitors: On Track to Tackle Tuberculosis
Chem. Proc. 2022, 12(1), 78; https://doi.org/10.3390/ecsoc-26-13688 - 17 Nov 2022
Viewed by 831
Abstract
The WHO database shows that mycobacterium tuberculosis has become an epidemic worldwide due to its pathogenicity and virulence, which have magnified its infectiousness. The situation becomes grimmer with the prevalence of MDR-TB, XDR-TB, emergence of cross-resistance, ineffectiveness of novel therapeutic targets, failure of [...] Read more.
The WHO database shows that mycobacterium tuberculosis has become an epidemic worldwide due to its pathogenicity and virulence, which have magnified its infectiousness. The situation becomes grimmer with the prevalence of MDR-TB, XDR-TB, emergence of cross-resistance, ineffectiveness of novel therapeutic targets, failure of novel medications in clinical trials, currently available drugs losing their therapeutic efficacy, lack of drug discovery efforts due to poor ROI, and the existence of co-infections; i.e., HIV, TB, COVID, and HIV-TB-COVID. Following our prior studies described by Stirret et al. in 2008, Ferreras et al. in 2011, and Shyam et al. in 2021, herein we focus on exploring pyrazoline-based mycobactin analogs (non-specific mycobactin biosynthesis inhibitors) targeting the MbtA enzyme (first step of mycobactin biosynthesis) with a hope of finding a more potent analog showing a high affinity for MbtA. The design strategy involves retaining the structural features of mycobacterial siderophores. Herein, a small library (12 molecules) of mycobactin analogs were designed, keeping the necessary skeleton (diaryl-substituted pyrazoline (DAP)) intact and assessed their stability using in silico tools. In order to determine the binding modes and inhibitory profiles of the designed ligands, docking was carried out in the active pocket of MbtA (analogous with the homologous structure with PDB ID: 1MDB). The best energy conformation (lowest score) of each docked ligand was represented graphically. The ADMET profile of each molecule was analyzed. The best molecule that revealed a good ADMET profile was taken up for MD simulation study (45 ns). Results revealed that the designed compounds GV08 (−8.80 kcal/mol, 352.58 nM), GV09 (−8.61 kcal/mol, 499.91 nM), GV03 (−8.59 kcal/mol, 508.51 nM), and GV07 (−8.54 kcal/mol, 553.44 nM) had a good docking score and inhibition constant. Of these, GV08 showed a good ADME profile with all the major parameters lying in the acceptable ranges. They also showed the least toxicity with no hepatotoxicity and skin sensitization. MD simulation studies of GV08 also suggest that it was stable throughout the course of simulation. This could be justified by RMSD, RMSF, and H-bond plots. The future scope invalidates these findings through synthesis, characterization, and intracellular activity. Full article
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6 pages, 1456 KiB  
Proceeding Paper
A One Pot Synthesis of Diketopiperazines via Multicomponent Reactions Based on Isocyanides
Chem. Proc. 2022, 12(1), 79; https://doi.org/10.3390/ecsoc-26-13648 - 16 Nov 2022
Viewed by 772
Abstract
2,5-DKPs are heterocyclic peptidomimetics, present in nature with high structural diversity, popular in the design of new bioactive molecules with potential application in medicinal chemistry, exhibiting anticancer and antimicrobial properties, among others. Therefore, in the present work, we report the one-pot synthesis of [...] Read more.
2,5-DKPs are heterocyclic peptidomimetics, present in nature with high structural diversity, popular in the design of new bioactive molecules with potential application in medicinal chemistry, exhibiting anticancer and antimicrobial properties, among others. Therefore, in the present work, we report the one-pot synthesis of 2,5-DKPs and their links to another heterocycle 1,4-disubstituted 1,2,3-triazole under mild reaction conditions by one-pot process via the sequence IMCR/postransformation/CuAAC with several advantages over previously reported conventional methods. Full article
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5 pages, 4543 KiB  
Proceeding Paper
A Modified Silver–Egg Shell Nanocomposite Applied for Antibacterial Activities
Chem. Proc. 2022, 12(1), 80; https://doi.org/10.3390/ecsoc-26-13580 - 14 Nov 2022
Viewed by 849
Abstract
Bacterial infections have extensive impacts on public health. Therefore, finding compounds with antibacterial properties could serve as an effective method. A nanocomposite, Ag/CaO, was prepared from silver nitrate and egg shells. After calcination of the egg shells, the remaining solid, CaO, was cooled; [...] Read more.
Bacterial infections have extensive impacts on public health. Therefore, finding compounds with antibacterial properties could serve as an effective method. A nanocomposite, Ag/CaO, was prepared from silver nitrate and egg shells. After calcination of the egg shells, the remaining solid, CaO, was cooled; then, silver nitrate was added and the mixture was ground to a fine powder, and finally heated to 300 °C. The brown solid obtained was characterized by XRD, SEM and XRF methods. The prepared Ag/CaO was examined for antibacterial activity against Gram-positive and Gram-negative bacteria, including Keleb pneumonia, staphylococcus aureus, and Escherichia coli. We previously published a similar paper in the 25th ECSOC 2021, but the current paper has two changes, including the amount of silver nitrate and calcium oxide in the synthesis route, and the size of the first synthesized nanocomposite by grinding with a ball mill; then, we examined these two substances against the bacteria. In fact, changing the amount of silver, known as the antibacterial metal, was compared to changing the size of the nanocomposite, which could have a greater antibacterial effect. Full article
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6 pages, 1089 KiB  
Proceeding Paper
I2-Catalyzed/DMSO System for the Oxidation of Se-Se Bond Activated by the Use of SynLED Parallel Photoreactor®
Chem. Proc. 2022, 12(1), 81; https://doi.org/10.3390/ecsoc-26-13562 - 14 Nov 2022
Viewed by 788
Abstract
Among the different green oxidative protocols, I2-catalyzed/DMSO systems have recently received considerable attention due to being greener, efficient, atom-economical, low-cost, and offering the possibility to perform reactions under safe and mild conditions. Of particular interest is their application in the chalcogen–chalcogen [...] Read more.
Among the different green oxidative protocols, I2-catalyzed/DMSO systems have recently received considerable attention due to being greener, efficient, atom-economical, low-cost, and offering the possibility to perform reactions under safe and mild conditions. Of particular interest is their application in the chalcogen–chalcogen bond activation that allows for the in situ formation of electrophilic species, promoting the formation of a number of Se-C bonds. Iodine acts as a catalytic oxidant in these reactions and is continuously regenerated by the DMSO, which can be used in stoichiometric amounts under solvent-free conditions. Methoxyselenylation reactions can be performed at room temperature; however, the reaction takes over 24 h to reach appreciable conversion yields. In this paper, activation by the use of a SynLED Parallel Photoreactor® is investigated as an alternative energy source, and the results are critically compared with those previously reported in literature. Full article
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8 pages, 2397 KiB  
Proceeding Paper
Potential Fluorescent Ligands for Zn-Containing Bacterial Enzymes: In Silico Evaluation, Synthesis and Optical Properties
Chem. Proc. 2022, 12(1), 82; https://doi.org/10.3390/ecsoc-26-13685 - 17 Nov 2022
Viewed by 727
Abstract
Zn-containing proteins play essential roles in the viability and virulence of bacteria, so are considered to be possible molecular new drug targets. Based on literature data about N-acyl-o-phenylenediamine and 2-pycolylamine as warheads of drugs and molecular probes for Zn-bearing enzymes like histone [...] Read more.
Zn-containing proteins play essential roles in the viability and virulence of bacteria, so are considered to be possible molecular new drug targets. Based on literature data about N-acyl-o-phenylenediamine and 2-pycolylamine as warheads of drugs and molecular probes for Zn-bearing enzymes like histone deacetylases, we guessed that N-(7-nitrobenzofurazan-4-y)-o-phenylenediamine (NBD-OPD), 2-pycolyl-(N-(7-nitrobenzofurazan-4-amine)) and ciprofloxacin 2-pycolylamide (CPF-Pic2) are potential fluorescent inhibitors of such enzymes. Molecular docking was performed for estimate affinity of the compounds to a set of bacterial enzymes, and photochemical and electrochemical properties were calculated in silico using DFT. Full article
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4 pages, 541 KiB  
Proceeding Paper
Electrochemical Synthesis of Imidazopyridine and Benzylidene Malononitrile
Chem. Proc. 2022, 12(1), 83; https://doi.org/10.3390/ecsoc-26-13567 - 14 Nov 2022
Viewed by 692
Abstract
A one-pot electrochemical synthesis of two medically interesting compounds is presented. 2-Phenylimidazo[1,2-a]pyridine and 2-(4-fluorobenzylidene)malononitrile were prepared using previously used starting materials. The reaction consists of electrochemical methods without adding additional reagents, giving product yields of about 82–90% at 5.0 V, leading to a [...] Read more.
A one-pot electrochemical synthesis of two medically interesting compounds is presented. 2-Phenylimidazo[1,2-a]pyridine and 2-(4-fluorobenzylidene)malononitrile were prepared using previously used starting materials. The reaction consists of electrochemical methods without adding additional reagents, giving product yields of about 82–90% at 5.0 V, leading to a different approach for synthesizing important organic compounds with efficient route. Full article
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3 pages, 343 KiB  
Proceeding Paper
Microwave Activation in Fe-Catalyzed Reaction of Binor-S with Nitriles
Chem. Proc. 2022, 12(1), 84; https://doi.org/10.3390/ecsoc-26-13676 - 17 Nov 2022
Viewed by 826
Abstract
An efficient catalytic system consisting of 20 mol. % FeCl3·6H2O and 20 mol. % trifluoromethanesulfonic acid for the amidation of binor-S in a solution of toluene with organic nitriles under the action of microwave irradiation at 100 °C for [...] Read more.
An efficient catalytic system consisting of 20 mol. % FeCl3·6H2O and 20 mol. % trifluoromethanesulfonic acid for the amidation of binor-S in a solution of toluene with organic nitriles under the action of microwave irradiation at 100 °C for 30 min was developed. Full article
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7 pages, 1211 KiB  
Proceeding Paper
Use of Phenyl Formate as a CO Surrogate for the Reductive Cyclization of Organic Nitro Compounds to Yield Different N-Heterocycles: Avoiding the Use of Autoclaves and Pressurized Gases
Chem. Proc. 2022, 12(1), 85; https://doi.org/10.3390/ecsoc-26-13711 - 18 Nov 2022
Viewed by 983
Abstract
The reductive cyclization of different organic nitro compounds by carbon monoxide, catalyzed by transition metal complexes, is a very efficient and clean strategy for the synthesis of many N-heterocycles. However, it requires the use of autoclaves and pressurized CO lines. In this [...] Read more.
The reductive cyclization of different organic nitro compounds by carbon monoxide, catalyzed by transition metal complexes, is a very efficient and clean strategy for the synthesis of many N-heterocycles. However, it requires the use of autoclaves and pressurized CO lines. In this paper, the authors will present the results obtained in their laboratories on the use of phenyl formate as a convenient CO surrogate, able to liberate carbon monoxide under reaction conditions and allowing for the use of a cheap glass pressure tube as a reaction vessel. In most cases, yields were better than those previously reported using pressurized CO, proving that the use of CO surrogates can be a viable alternative to the gaseous reagent. Full article
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5 pages, 4031 KiB  
Proceeding Paper
In Silico Modeling of the Interaction of NBD Steroids with Insect Steroid-Binding Protein SPC-2
Chem. Proc. 2022, 12(1), 86; https://doi.org/10.3390/ecsoc-26-13712 - 18 Nov 2022
Viewed by 1044
Abstract
Two fluorescent sterol-like molecules have been synthesized, namely, a derivative of 7-nitrobenzofurazan (NBD) with 17-(methylamino)-androst-5-en-3beta-ol (DAM-NBD) and NBD-piperazine conjugate with cholesteryl chloroformate (NBD-pip-CCF). In silico docking and plasma membrane simulations have shown ability of the compounds to penetrate the lipid bilayer, as well [...] Read more.
Two fluorescent sterol-like molecules have been synthesized, namely, a derivative of 7-nitrobenzofurazan (NBD) with 17-(methylamino)-androst-5-en-3beta-ol (DAM-NBD) and NBD-piperazine conjugate with cholesteryl chloroformate (NBD-pip-CCF). In silico docking and plasma membrane simulations have shown ability of the compounds to penetrate the lipid bilayer, as well as to bind affinely of the yellow fever mosquito SCP-2 protein structure (code PDB: 3BDQ; binding energy about −11.9 kcal/mol). Also docking with AlphaFOLD-predicted insect Neverland protein structure demonstrated DAM-NBD binding with a similar affinity. The theoretical results indicate perspectives of the fluorescent steroid usage to study insect protein-sterol interactions. Full article
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6 pages, 1381 KiB  
Proceeding Paper
High-Throughput Virtual Screening of Compounds with Electrophilic Fragments for New Potential Covalent Inhibitors of Bacterial Proteins
Chem. Proc. 2022, 12(1), 87; https://doi.org/10.3390/ecsoc-26-13574 - 14 Nov 2022
Cited by 1 | Viewed by 641
Abstract
The search for new antibacterial drugs has continued to be an urgent matter. One of the approaches is the development of covalent inhibitors using biochemoinformatics at the initial stages. In this work, structures of a few plant-derived substances with electrophilic unsaturated carbonyl and [...] Read more.
The search for new antibacterial drugs has continued to be an urgent matter. One of the approaches is the development of covalent inhibitors using biochemoinformatics at the initial stages. In this work, structures of a few plant-derived substances with electrophilic unsaturated carbonyl and structures of small synthetic compounds suitable for fragment-based drug discovery (FBDD) with -CH2-Br group were selected as ligands for sets of structures of bacterial proteins. The theoretical assessment was carried out using the Autodock Vina program for calculation and FYTdock for the organization of the process and the analysis of results. Natural Ixerine D as well as synthetic 4-(4-(2-bromoethyl)piperazin-1-yl)-7-nitrobenzofurazan demonstrated the most promising results as potential Cys-targeted inhibitors. Full article
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3 pages, 213 KiB  
Proceeding Paper
Theoretical Studies and Computer Modeling of Supramolecular Chemical Systems: Structure, Properties and Reactivity
Chem. Proc. 2022, 12(1), 88; https://doi.org/10.3390/ecsoc-26-13717 - 18 Nov 2022
Viewed by 892
Abstract
The results of my research in the fields of theoretical studies and computer modeling of supramolecular chemical systems were presented. The main attention was focused on theoretical studies in the following topics: cycloaddition and nucleophilic addition reactions involving substrates with multiple CC and [...] Read more.
The results of my research in the fields of theoretical studies and computer modeling of supramolecular chemical systems were presented. The main attention was focused on theoretical studies in the following topics: cycloaddition and nucleophilic addition reactions involving substrates with multiple CC and CN bonds, their mechanisms, driving forces, kinetics and thermodynamics; the consideration of the catalysis of hydrocarbons oxidation processes and their conversion to alcohols, ethers, aldehydes, ketones and carboxylic acids; investigations of various unusual types of non-covalent interactions (from quite trivial hydrogen bonds to more exotic σ-hole, π-hole and metallophilic interactions) in organic, organometallic and coordination compounds. Some fundamental issues of supramolecular chemical systems were also discussed (e.g., structure and properties of chemical compounds and their supramolecular associates; conformational transitions and rotation barriers of functional groups; nature of chemical bonds; orbital and charge factors; photophysical properties). Full article
4 pages, 481 KiB  
Proceeding Paper
Multiple Pathways in Cp2TiCl2—Catalyzed Reaction of Tetraalkyl-Substituted Pyrazines with EtAlCl2 and Mg
Chem. Proc. 2022, 12(1), 89; https://doi.org/10.3390/ecsoc-26-13709 - 18 Nov 2022
Viewed by 1053
Abstract
There exist a number of classical methods for the synthesis of substituted pyrazines. Among this variety of reactions, the synthesis of substituted pyrazines from nitriles does not stand out in either the number of known examples or in product yield. However, the one-stage [...] Read more.
There exist a number of classical methods for the synthesis of substituted pyrazines. Among this variety of reactions, the synthesis of substituted pyrazines from nitriles does not stand out in either the number of known examples or in product yield. However, the one-stage character of the transformation, together with the uncertainty of its mechanism, aroused our interest in this catalytic reaction. Here, we report the successful implementation of the Cp2TiCl2-catalyzed reaction of aliphatic nitriles with EtAlCl2 and Mg, which led to the selective preparation of 2,3,5,6-tetraalkyl-substituted pyrazines, 2,4,5-trisubstituted-1H-imidazole or 2-aminocyclopent-1-ene-carbonitrile depending on reaction conditions and substituents. Full article
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7 pages, 1064 KiB  
Proceeding Paper
Synthesis of Carboxymethyl Chitosan and Its Derivatives Using KI and/or Ultrasonication
Chem. Proc. 2022, 12(1), 90; https://doi.org/10.3390/ecsoc-26-13644 - 26 Nov 2022
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Abstract
Chitosan is a natural polysaccharide that is mainly obtained from the shell of marine crustaceans including crabs, lobsters, shrimps, etc. Chitosan has been widely used in biomedicine due to its special characteristics of low toxicity, biocompatibility, biodegradation, and low immunogenicity. However, owing to [...] Read more.
Chitosan is a natural polysaccharide that is mainly obtained from the shell of marine crustaceans including crabs, lobsters, shrimps, etc. Chitosan has been widely used in biomedicine due to its special characteristics of low toxicity, biocompatibility, biodegradation, and low immunogenicity. However, owing to the limited solubility of CS in water, its water-soluble derivatives are preferred for the mentioned applications. Carboxymethyl chitosan (CMC) is one of the water-soluble derivatives of chitosan, which has antibacterial, anticancer, antitumor, antifungal, antioxidant properties, and is used in both drug delivery and enzyme delivery. This material is also utilized in tissue engineering, wound healing, and bioimaging. For these reasons, in this article, a different and novel method by using KI and/or ultrasonication is proposed. Full article
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7 pages, 862 KiB  
Proceeding Paper
Nanoencapsulation of 3-Chloropropylaminobenzoate Derivatives with Potential Insecticidal Activity
Chem. Proc. 2022, 12(1), 91; https://doi.org/10.3390/ecsoc-26-13719 - 18 Nov 2022
Viewed by 910
Abstract
Aminobenzoic acid derivatives have shown various pharmacological properties, one of which is pesticide activity, giving these compounds the ability to work as alternatives to current pesticides. Nanotechnology could efficiently support the use of these compounds by encapsulating them in stable nanoformulations to improve [...] Read more.
Aminobenzoic acid derivatives have shown various pharmacological properties, one of which is pesticide activity, giving these compounds the ability to work as alternatives to current pesticides. Nanotechnology could efficiently support the use of these compounds by encapsulating them in stable nanoformulations to improve their stability and effectiveness. In the present work, 3-chloropropylaminobenzoate derivatives were synthesised and evaluated against their effect on the viability of the insect cell line Sf9 (Spodoptera frugiperda), and nanoencapsulation studies of the most active compound were carried out. The most potent molecules reduced insect cell viability by around 40% at 100 µg/mL. Full article
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7 pages, 2224 KiB  
Proceeding Paper
Immobilization on Cellulose Paper of a Chemosensor for CdSe-Cys QDs
Chem. Proc. 2022, 12(1), 92; https://doi.org/10.3390/ecsoc-26-13561 - 14 Nov 2022
Viewed by 542
Abstract
The Schiff base ligand H2SB derived from the condensation of N-(2-aminobenzyl)-5-(dimethylamino)naphthalene-1-sulfonamide with 4-formyl-3-hydroxybenzoic acid has been investigated as a chemosensor for the detection of CdSe-Cys QDs in water samples. We immobilized H2SB onto cellulose paper by forming an [...] Read more.
The Schiff base ligand H2SB derived from the condensation of N-(2-aminobenzyl)-5-(dimethylamino)naphthalene-1-sulfonamide with 4-formyl-3-hydroxybenzoic acid has been investigated as a chemosensor for the detection of CdSe-Cys QDs in water samples. We immobilized H2SB onto cellulose paper by forming an amide bond, which results from the condensation of a carboxylic acid and an amine. Three dominant signals located around 270, 330, and 420 nm in the diffuse reflectance spectrum of the H2SB-modified paper demonstrated its immobilization. A linear decrease can be observed in the absorbance of the 270 nm band with the increase of the CdSe-Cys QDs concentration from 100 ppb to 2 ppm. The LOD and LOQ show values of 245 and 815 ppb, respectively. An interaction via metal–ligand coordination between CdSe-Cys QDs and H2SB has been demonstrated with 1H NMR, ATR-FTIR, and UV-Vis spectroscopy. Full article
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