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Keywords = Gewald

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19 pages, 556 KB  
Review
Transforming Stroke Diagnosis with Artificial Intelligence: A Scoping Review of Brainomix e-Stroke, Aidoc, RapidAI, and Viz.ai
by Mateusz Dorochowicz, Arkadiusz Kacała, Aleksandra Tołkacz, Aleksandra Kosikowska, Maja Gewald and Maciej Guziński
Medicina 2026, 62(3), 582; https://doi.org/10.3390/medicina62030582 - 19 Mar 2026
Viewed by 1114
Abstract
Background and Objectives: Rapid diagnosis is fundamental to acute ischemic stroke management; however, access to neuroradiological expertise remains limited. This scoping review maps the diagnostic accuracy, workflow impact, and cost-effectiveness of leading AI platforms (Brainomix, Aidoc, RapidAI, and Viz.ai), characterizing industry and [...] Read more.
Background and Objectives: Rapid diagnosis is fundamental to acute ischemic stroke management; however, access to neuroradiological expertise remains limited. This scoping review maps the diagnostic accuracy, workflow impact, and cost-effectiveness of leading AI platforms (Brainomix, Aidoc, RapidAI, and Viz.ai), characterizing industry and peer-reviewed metrics. Materials and Methods: Following PRISMA-ScR guidelines, we searched PubMed, Cochrane Library, and HTA repositories for studies (2019–2025). Using a PICO-based framework, 29 studies were included for thematic mapping of the technological landscape. Results: Twenty-nine studies were included. Platforms show high proximal LVO sensitivity (78–97%), while performance for distal/MVO and posterior circulation occlusions was more variable. RapidAI is frequently mapped using historical perfusion trial parameters; however, volumetric discrepancies with platforms like Viz.ai indicate outputs are not interchangeable. Brainomix shows extensive validation for automated NCCT ASPECTS in triage. Aidoc demonstrates operational advantages via worklist prioritization, while. Viz.ai is associated with door-to-puncture time reductions (11–25 min). Economically, cost-effectiveness is driven by improved functional outcomes and expanded access to thrombectomy, rather than labor substitution. Conclusions: AI platforms function as diagnostic safety nets and workflow optimizers. Reported roles, such as perfusion-centric analysis (RapidAI) or workflow coordination (Viz.ai), reflect current research trends rather than definitive technological superiority. Institutional selection should consider these evidence clusters alongside local validation and specific clinical priorities. Full article
(This article belongs to the Special Issue AI in Imaging—New Perspectives, 2nd Edition)
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7 pages, 458 KB  
Communication
Synthesis of Ethyl 2-Amino-6-hydroxy-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate and Ethyl 6-(Acetyloxy)-2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate
by Andrii Yu. Myshastyi, Sergiy V. Vlasov, Hanna I. Severina, Georgiy G. Yakovenko and Andrii R. Khairulin
Molbank 2026, 2026(2), M2144; https://doi.org/10.3390/M2144 - 4 Mar 2026
Viewed by 705
Abstract
An effective one-step synthetic procedure for preparation of hydroxylated analogues of ethyl 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate as novel promising multifunctional building blocks for drug discovery based on the Gewald procedure was developed. Full article
(This article belongs to the Section Organic Synthesis and Biosynthesis)
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26 pages, 3201 KB  
Article
In Vitro Evaluation of Sugar-Conjugated Thienopyrimidinone Derivatives with Possible Neuroprotective and Antioxidant Effects
by Asma K. Alshamari, Wael M. Aboulthana, Hayam Mansour, Khadiga M. Abu-Zied, Odeh A. O. Alshammari, Nesrin M. Morsy, Nuha O. S. Alsaif, Mona Z. Alshammari, Eman S. Nossier and Nasser A. Hassan
Int. J. Mol. Sci. 2025, 26(22), 10826; https://doi.org/10.3390/ijms262210826 - 7 Nov 2025
Cited by 1 | Viewed by 763
Abstract
A series of glycosylated thienopyrimidinone derivatives (7a–e and 8a–e), previously synthesized through a multi-step sequence involving a Gewald reaction, thiocyanate cyclization, functionalization with chloroacetic acid, and subsequent coupling with aldose sugars (glucose, mannose, galactose, xylose, and arabinose), were subjected to comprehensive [...] Read more.
A series of glycosylated thienopyrimidinone derivatives (7a–e and 8a–e), previously synthesized through a multi-step sequence involving a Gewald reaction, thiocyanate cyclization, functionalization with chloroacetic acid, and subsequent coupling with aldose sugars (glucose, mannose, galactose, xylose, and arabinose), were subjected to comprehensive biological evaluation. Structural confirmation of all compounds was achieved by spectroscopic and elemental analyses. Among them, compound 8e displayed remarkable antioxidant capacity, with radical scavenging activity surpassing standard controls, and demonstrated significant neuroprotective potential through its ability to attenuate oxidative stress, a key driver of neurodegeneration. Furthermore, 8e exhibited notable anti-arthritic and anti-diabetic effects, which may indirectly enhance neuroprotection by alleviating systemic inflammation and metabolic dysfunction—recognized risk factors for neurodegenerative disorders. Molecular docking and molecular dynamics studies revealed favorable binding interactions and structural stability of 8e with multiple biological targets, supporting its promise as a multifunctional neuroprotective candidate against oxidative stress and neurodegeneration. Full article
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33 pages, 2593 KB  
Article
Synthesis of New Phenothiazine/3-cyanoquinoline and Phenothiazine/3-aminothieno[2,3-b]pyridine(-quinoline) Heterodimers
by Victor V. Dotsenko, Vladislav K. Kindop, Vyacheslav K. Kindop, Eva S. Daus, Igor V. Yudaev, Yuliia V. Daus, Alexander V. Bespalov, Dmitrii S. Buryi, Darya Yu. Lukina, Nicolai A. Aksenov and Inna V. Aksenova
Int. J. Mol. Sci. 2025, 26(19), 9798; https://doi.org/10.3390/ijms26199798 - 8 Oct 2025
Cited by 2 | Viewed by 2460
Abstract
The aim of this work was to prepare new heterodimeric molecules containing pharmacophoric fragments of 3-cyanoquinoline/3-aminothieno[2,3-b]pyridine/3-aminothieno[2,3-b]quinoline on one side and phenothiazine on the other. The products were synthesized via selective S-alkylation of readily available 2-thioxo-3-cyanopyridines or -quinolines with N-(chloroacetyl)phenothiazines, followed by base-promoted Thorpe–Ziegler [...] Read more.
The aim of this work was to prepare new heterodimeric molecules containing pharmacophoric fragments of 3-cyanoquinoline/3-aminothieno[2,3-b]pyridine/3-aminothieno[2,3-b]quinoline on one side and phenothiazine on the other. The products were synthesized via selective S-alkylation of readily available 2-thioxo-3-cyanopyridines or -quinolines with N-(chloroacetyl)phenothiazines, followed by base-promoted Thorpe–Ziegler isomerization of the resulting N-[(3-cyanopyridin-2-ylthio)acetyl]phenothiazines. We found that both the S-alkylation and the Thorpe–Ziegler cyclization reactions, when conducted with KOH under heating, were accompanied to a significant extent by a side reaction involving the elimination of phenothiazine. Optimization of the conditions (0–5 °C, anhydrous N,N-dimethylacetamide and NaH or t-BuONa as non-nucleophilic bases) minimized the side reaction and increased the yields of the target heterodimers. The structures of the products were confirmed by IR spectroscopy, 1H, and 13C DEPTQ NMR studies. It was demonstrated that the synthesized 3-aminothieno[2,3-b]pyridines can be acylated with chloroacetyl chloride in hot chloroform. The resulting chloroacetamide derivative reacts with potassium thiocyanate in DMF to form the corresponding 2-iminothiazolidin-4-one; in this process, phenothiazine elimination does not occur, and the Gruner–Gewald rearrangement product was not observed. The structural features and spectral characteristics of the synthesized 2-iminothiazolidin-4-one derivative were investigated by quantum chemical methods at the B3LYP-D4/def2-TZVP level. A range of drug-relevant properties was also evaluated using in silico methods, and ADMET parameters were calculated. A molecular docking study identified a number of potential protein targets for the new heterodimers, indicating the promise of these compounds for the development of novel antitumor agents. Full article
(This article belongs to the Section Molecular Pharmacology)
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21 pages, 8490 KB  
Article
2-Aminothiophene Derivatives—New Drug Candidates Against Leishmaniasis: Drug Design, Synthesis, Pharmacomodulation, and Antileishmanial Activity
by Rodrigo Santos Aquino de Araújo, Vitória Gaspar Bernardo, Robert da Silva Tibúrcio, Danilo Cesar Galindo Bedor, Michel Leandro de Campos, Roberto Pontarolo, Julyanne Maria Saraiva de Sousa, Klinger Antonio da Franca Rodrigues, Marcus Tullius Scotti, Anuraj Nayarisseri, Pascal Marchand and Francisco Jaime Bezerra Mendonça-Junior
Pharmaceuticals 2025, 18(1), 125; https://doi.org/10.3390/ph18010125 - 17 Jan 2025
Cited by 6 | Viewed by 3821
Abstract
Background/Objectives: Leishmaniasis is one of the 20 Neglected Tropical Diseases according to the WHO, affecting approximately 12 million people in four continents, generating serious public health problems. The lack of therapeutic options, associated with toxicity and the emergence of resistance to the [...] Read more.
Background/Objectives: Leishmaniasis is one of the 20 Neglected Tropical Diseases according to the WHO, affecting approximately 12 million people in four continents, generating serious public health problems. The lack of therapeutic options, associated with toxicity and the emergence of resistance to the few available drugs, makes it urgent to develop new drug options. In this context, the aims of this work are to expand the knowledge about the pharmacophore group responsible for the antileishmanial potential of 2-aminothiophene derivatives. Thus, new compounds were synthesized containing chemical modifications at the C-3, C-4, and C-5 positions of the 2-aminothiophene ring, in addition to the S-Se bioisosterism. Methods: Dozens of 2-AT and 2-aminoselenophen (2-AS) derivatives were sequentially synthesized through applications of the Gewald reaction and were then evaluated in vitro for their activities against L. amazonensis and for cytotoxicity against macrophages. Results: Several series of compounds were synthesized, and it was possible to identify some substitution patterns favorable to the activity generating compounds with IC50 values below 10 µM, such as the non-essentiality of the presence of a carbonitrile group at C-3; the importance of the presence and size of cycloalkyl/piperidinyl chains at C-4 and C-5 in modulating the activity; and the increase in activity without affecting the safety of the S/Se bioisosteric substitution. Conclusions: Taken together, these findings reaffirm the great potential of 2-aminothiophenes to generate antileishmanial drug candidates and offers contributions to the drug design of compounds with an even more promising profile for the problem of leishmaniasis. Full article
(This article belongs to the Special Issue Drug Discovery of Antiprotozoal Agents 2024)
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42 pages, 13456 KB  
Review
Multicomponent Reactions for the Synthesis of Active Pharmaceutical Ingredients
by Ángel Cores, José Clerigué, Emmanuel Orocio-Rodríguez and J. Carlos Menéndez
Pharmaceuticals 2022, 15(8), 1009; https://doi.org/10.3390/ph15081009 - 17 Aug 2022
Cited by 73 | Viewed by 14927
Abstract
Multicomponent reactions 9i.e., those that engage three or more starting materials to form a product that contains significant fragments of all of them), have been widely employed in the construction of compound libraries, especially in the context of diversity-oriented synthesis. While relatively less [...] Read more.
Multicomponent reactions 9i.e., those that engage three or more starting materials to form a product that contains significant fragments of all of them), have been widely employed in the construction of compound libraries, especially in the context of diversity-oriented synthesis. While relatively less exploited, their use in target-oriented synthesis offers significant advantages in terms of synthetic efficiency. This review provides a critical summary of the use of multicomponent reactions for the preparation of active pharmaceutical principles. Full article
(This article belongs to the Special Issue Multicomponent and Domino Reactions in Drug Discovery)
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21 pages, 4291 KB  
Article
Design, Synthesis, and Biological Evaluation of 5,6,7,8-Tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidines as Microtubule Targeting Agents
by Farhana Islam, Arpit Doshi, Andrew J. Robles, Tasdique M. Quadery, Xin Zhang, Xilin Zhou, Ernest Hamel, Susan L. Mooberry and Aleem Gangjee
Molecules 2022, 27(1), 321; https://doi.org/10.3390/molecules27010321 - 5 Jan 2022
Cited by 9 | Viewed by 6952
Abstract
A series of eleven 4-substituted 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidines were designed and synthesized and their biological activities were evaluated. Synthesis involved the Gewald reaction to synthesize ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate ring, and SNAr reactions. Compound 4 was 1.6- and ~7-fold more potent than the [...] Read more.
A series of eleven 4-substituted 5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidines were designed and synthesized and their biological activities were evaluated. Synthesis involved the Gewald reaction to synthesize ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate ring, and SNAr reactions. Compound 4 was 1.6- and ~7-fold more potent than the lead compound 1 in cell proliferation and microtubule depolymerization assays, respectively. Compounds 4, 5 and 7 showed the most potent antiproliferative effects (IC50 values < 40 nM), while compounds 6, 8, 10, 12 and 13 had lower antiproliferative potencies (IC50 values of 53–125 nM). Additionally, compounds 48, 10 and 1213 circumvented Pgp and βIII-tubulin mediated drug resistance, mechanisms that diminish the clinical efficacy of paclitaxel (PTX). In the NCI-60 cell line panel, compound 4 exhibited an average GI50 of ~10 nM in the 40 most sensitive cell lines. Compound 4 demonstrated statistically significant antitumor effects in a murine MDA-MB-435 xenograft model. Full article
(This article belongs to the Special Issue Design, Synthesis and Applications of New Anti-cancer Agents II)
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17 pages, 5846 KB  
Article
Investigation of the Effects of Charging Processes on Lithium-Ion Cells with SiC Anodes at Low Temperatures
by Ralph Bednorz and Tanja Gewald
Batteries 2020, 6(2), 34; https://doi.org/10.3390/batteries6020034 - 18 Jun 2020
Cited by 13 | Viewed by 6927
Abstract
Lithium-ion cells with a silicon-graphite (SiC) anode and a nickel-rich cathode are potential candidates for use in electric vehicles (EVs) as this material combination offers high energy densities and low costs. Another desired cell specification that results from an intended short charging time [...] Read more.
Lithium-ion cells with a silicon-graphite (SiC) anode and a nickel-rich cathode are potential candidates for use in electric vehicles (EVs) as this material combination offers high energy densities and low costs. Another desired cell specification that results from an intended short charging time for EVs is the robustness against high charge rates. However, high charge rates can lead to the critical aging mechanism of lithium plating, especially at low temperatures. Investigating this issue, this paper presents a test series on cyclic aging with varying charge rates from 0.2C to 1.5C at ambient temperatures of 0 °C and 10 °C applied to a nickel-rich SiC cell candidate. The resulting effects on cell aging are analyzed with a stripping method, whereby reversible lithium plating can be detected, and a differential voltage analysis (DVA), whereby the overall loss of capacity can be attributed to changes in individual characteristic capacities. The results indicate a degradation sensitivity of SiC anodes at elevated charge rates, evidenced by the loss in the silicon-related characteristic capacity, and question the aging robustness of this material combination. Full article
(This article belongs to the Special Issue Lithium-Ion Batteries Aging Mechanisms)
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18 pages, 5454 KB  
Article
Accelerated Aging Characterization of Lithium-ion Cells: Using Sensitivity Analysis to Identify the Stress Factors Relevant to Cyclic Aging
by Tanja Gewald, Adrian Candussio, Leo Wildfeuer, Dirk Lehmkuhl, Alexander Hahn and Markus Lienkamp
Batteries 2020, 6(1), 6; https://doi.org/10.3390/batteries6010006 - 20 Jan 2020
Cited by 36 | Viewed by 15458
Abstract
As storage technology in electric vehicles, lithium-ion cells are subject to a continuous aging process during their service life that, in the worst case, can lead to a premature system failure. Battery manufacturers thus have an interest in the aging prediction during the [...] Read more.
As storage technology in electric vehicles, lithium-ion cells are subject to a continuous aging process during their service life that, in the worst case, can lead to a premature system failure. Battery manufacturers thus have an interest in the aging prediction during the early design phase, for which semi-empirical aging models are often used. The progress of aging is dependent on the application-specific load profile, more precisely on the aging-relevant stress factors. Still, a literature review reveals a controversy on the aging-relevant stress factors to use as input parameters for the simulation models. It shows that, at present, a systematic and efficient procedure for stress factor selection is missing, as the aging characteristic is cell-specific. In this study, an accelerated sensitivity analysis as a prior step to aging modeling is proposed, which is transferable and allows to determine the actual aging-relevant stress factors for a specific lithium-ion cell. For the assessment of this accelerated approach, two test series with different acceleration levels and cell types are performed and evaluated. The results show that a certain amount of charge throughput, 100 equivalent full cycles in this case, is necessary to conduct a statistically significant sensitivity analysis. Full article
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9 pages, 245 KB  
Article
A Solvent-Free, One-Step, One-Pot Gewald Reaction for Alkyl-aryl Ketones via Mechanochemistry
by William C. Shearouse, Maxwell Z. Shumba and James Mack
Appl. Sci. 2014, 4(2), 171-179; https://doi.org/10.3390/app4020171 - 8 Apr 2014
Cited by 30 | Viewed by 13088
Abstract
Herein, we report on the solvent-free synthesis of 2-aminothiophenes via the Gewald reaction. Utilizing high speed ball milling conditions, we discovered the Gewald reaction can be catalytic in base, and conducted under aerobic conditions. Using thermal heat in tandem with the mixer/mill significantly [...] Read more.
Herein, we report on the solvent-free synthesis of 2-aminothiophenes via the Gewald reaction. Utilizing high speed ball milling conditions, we discovered the Gewald reaction can be catalytic in base, and conducted under aerobic conditions. Using thermal heat in tandem with the mixer/mill significantly increases the rate of reaction. Full article
(This article belongs to the Special Issue Greener and Sustainable Chemistry)
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15 pages, 380 KB  
Article
Synthesis and Biological Evaluation of Thiophene Derivatives as Acetylcholinesterase Inhibitors
by Mohamed M. Ismail, Mona M. Kamel, Lamia W. Mohamed, Samar I. Faggal and Mai A. Galal
Molecules 2012, 17(6), 7217-7231; https://doi.org/10.3390/molecules17067217 - 12 Jun 2012
Cited by 43 | Viewed by 6524
Abstract
A series of new thiophene derivatives has been synthesized using the Gewald protocol. The acetylcholinesterase inhibition activity was assayed according to Ellman’s method using donepezil as reference. Some of the compounds were found to be more potent inhibitors than the reference. 2-(2-(4-(4-Methoxyphenyl)piperazin-1-yl)acetamido)-4,5,6,7-tetrahydrobenzo[b [...] Read more.
A series of new thiophene derivatives has been synthesized using the Gewald protocol. The acetylcholinesterase inhibition activity was assayed according to Ellman’s method using donepezil as reference. Some of the compounds were found to be more potent inhibitors than the reference. 2-(2-(4-(4-Methoxyphenyl)piperazin-1-yl)acetamido)-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxamide (IIId) showed 60% inhibition, compared to only 40% inhibition by donepezil. Full article
(This article belongs to the Section Medicinal Chemistry)
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22 pages, 219 KB  
Article
Novel Synthesis and Antitumor Evaluation of Polyfunctionally Substituted Heterocyclic Compounds Derived from 2-Cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide
by Hoda Z. Shams, Rafat M. Mohareb, Maher H. Helal and Amira E. Mahmoud
Molecules 2011, 16(1), 52-73; https://doi.org/10.3390/molecules16010052 - 27 Dec 2010
Cited by 51 | Viewed by 12437
Abstract
The reaction of 2-amino-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene with ethyl cyanoacetate gave 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide. The latter was used to synthesize different heterocyclic derivatives comprising thiophene, thiazole, pyrazole, pyridine, pyrimidine, and coumarin rings. The mechanistic and synthetic pathways depended on regioselective attack and/or [...] Read more.
The reaction of 2-amino-3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophene with ethyl cyanoacetate gave 2-cyano-N-(3-cyano-4,5,6,7-tetrahydrobenzo[b]thiophen-2-yl)-acetamide. The latter was used to synthesize different heterocyclic derivatives comprising thiophene, thiazole, pyrazole, pyridine, pyrimidine, and coumarin rings. The mechanistic and synthetic pathways depended on regioselective attack and/or cyclization by the cyanoacetamido moiety in the key precursor on various chemical reagents. The competition of the reaction pathways including dipolar cyclization, dinucleophilic-bielectrophilic attack, β-attack, Gewald-type attack, and condensation reactions led to the diversity of the synthesized products. The antitumor activities of the synthesized products were studied and evaluated. Most of the compounds revealed high inhibitory effects when screened in vitro for their antiproliferative activity. Three human cancer cell lines, namely, breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) were used in the screening tests. The simplicity of the synthetic procedures which mainly involved one-pot reactions under mild reaction conditions, the convenience of yield production and the diversity of the reactive sites in the produced systems play a valuable role for further heterocyclic transformations and further biological investigations. Full article
(This article belongs to the Section Medicinal Chemistry)
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6 pages, 58 KB  
Communication
First Synthesis of 3-Acetyl-2-aminothiophenes Using the Gewald Reaction
by Gernot A. Eller and Wolfgang Holzer
Molecules 2006, 11(5), 371-376; https://doi.org/10.3390/11050371 - 16 May 2006
Cited by 37 | Viewed by 11796
Abstract
Novel 3-acetyl-2-aminothiophenes were prepared from cyanoacetone and1,4-dithianyl-2,5-diols using a modified Gewald reaction. The syntheses of thecorresponding acetamides, as well as that of 3-acetyl-2-amino-5-nitrothiophene – aninteresting building-block for thiophene azo dyes – are reported. Detailed spectroscopicinvestigations (1H-NMR, 13C-NMR, MS, IR) of [...] Read more.
Novel 3-acetyl-2-aminothiophenes were prepared from cyanoacetone and1,4-dithianyl-2,5-diols using a modified Gewald reaction. The syntheses of thecorresponding acetamides, as well as that of 3-acetyl-2-amino-5-nitrothiophene – aninteresting building-block for thiophene azo dyes – are reported. Detailed spectroscopicinvestigations (1H-NMR, 13C-NMR, MS, IR) of the obtained compounds are presented. Full article
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