Topical Collection "Heterocycle Reactions"

A topical collection in Molbank (ISSN 1422-8599). This collection belongs to the section "Organic Synthesis".

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Editor

Department of Pharmacy, School of Life Sciences, Pharmacy & Chemistry, Kingston University, Penrhyn Road, Kingston upon Thames KT1 2EE, UK
Interests: free radical organic and polymer chemistry; heterocyclic and medicinal chemistry
Special Issues, Collections and Topics in MDPI journals

Topical Collection Information

Dear Colleagues,

According to "Heterocyclic Chemistry" by J. A. Joule and K. Mills (Wiley, 5th Ed), "heterocyclic chemistry comprises at least half of all organic chemistry research worldwide". Many reactions proceed as predicted, while other reactions give unusual products, which perhaps do not fit the intended use but are nevertheless chemically interesting. Some reactions give more than one product, with selectivity tunable through optimization or biasing of reaction conditions. Often, interesting "side-products" are neglected in pursuit of a target compound.

This Special Issue welcomes the submission of any suitably fully characterized novel compound(s) from a given heterocyclic compound reaction. Please note that the reaction product does not necessarily have to be heterocyclic.

Prof. Dr. Fawaz Aldabbagh
Collection Editor

Manuscript Submission Information

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Keywords

  • Heterocyclic chemistry
  • Aromatic heterocycles
  • Non-aromatic heterocycles
  • Fused heterocycles
  • Nitrogen
  • Oxygen
  • Sulfur
  • Radical
  • Spectroscopic properties
  • Halogenation
  • Organic chemistry
  • Medicinal chemistry

Published Papers (63 papers)

2023

Jump to: 2022, 2021, 2020, 2019

Short Note
tert-Butyl (E)-3-oxo-2-(3-oxoisobenzofuran-1(3H)-ylidene)butanoate
Molbank 2023, 2023(2), M1614; https://doi.org/10.3390/M1614 - 30 Mar 2023
Viewed by 121
Abstract
Non-fullerene acceptors have recently attracted much attention as components of organic solar cells. 1H-indene-1,3(2H)-dione is a key compound for the synthesis of the end-capping component of non-fullerene acceptors. In this communication, an intermediate for the synthesis of this compound, [...] Read more.
Non-fullerene acceptors have recently attracted much attention as components of organic solar cells. 1H-indene-1,3(2H)-dione is a key compound for the synthesis of the end-capping component of non-fullerene acceptors. In this communication, an intermediate for the synthesis of this compound, tert-butyl (E)-3-oxo-2-(3-oxoisobenzofuran-1(3H)-ylidene)butanoate, was prepared by the reaction between phthalic anhydride and tert-butyl acetoacetate. Further treatment with sodium methoxide in methanol led to the formation of 1H-indene-1,3(2H)-dione in a high yield. The structure of the newly synthesized compound was established by means of elemental analysis, high-resolution mass spectrometry, 1H, 13C NMR, IR spectroscopy, mass spectrometry and X-ray analysis. Full article
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Short Note
New 2-(2,4-Dihydroxyphenyl)benzimidazolines
Molbank 2023, 2023(1), M1602; https://doi.org/10.3390/M1602 - 10 Mar 2023
Viewed by 314
Abstract
New 2-(2,4-dihydroxyphenyl)benzimidazolines are synthesized in an easily accessible approach. The method is based on the reaction of resorcinol with in situ-formed electrophilic N-ethoxycarbonylbenzimidazolium reagents. The structure of the two newly formed products was spectrally characterized by 1D and 2D NMR, IR, and [...] Read more.
New 2-(2,4-dihydroxyphenyl)benzimidazolines are synthesized in an easily accessible approach. The method is based on the reaction of resorcinol with in situ-formed electrophilic N-ethoxycarbonylbenzimidazolium reagents. The structure of the two newly formed products was spectrally characterized by 1D and 2D NMR, IR, and MS spectral analyses. Full article
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Short Note
4,4′-Difluoro-[3,3′-bi(1,2,5-oxadiazole)] 2,2′-Dioxide
Molbank 2023, 2023(1), M1596; https://doi.org/10.3390/M1596 - 23 Feb 2023
Viewed by 435
Abstract
1,2,5-Oxadiazole oxides (furoxans) are well known nitric oxide donors; among them, 4-fluorofuroxans have recently been found to be important photoinduced nitric oxide donors. In this research, it was shown that the reaction of 4,4′-dinitro-[3,3′-bi(1,2,5-oxadiazole)] 2,2′-dioxide with fluoro-containing reagents (tetrabutylammonium fluoride or cesium fluoride) [...] Read more.
1,2,5-Oxadiazole oxides (furoxans) are well known nitric oxide donors; among them, 4-fluorofuroxans have recently been found to be important photoinduced nitric oxide donors. In this research, it was shown that the reaction of 4,4′-dinitro-[3,3′-bi(1,2,5-oxadiazole)] 2,2′-dioxide with fluoro-containing reagents (tetrabutylammonium fluoride or cesium fluoride) selectively gave the bis-substitution product 4,4′-difluoro-[3,3′-bi(1,2,5-oxadiazole)] 2,2′-dioxide. The structure of the synthesized compound was established by elemental analysis, 13C, 19F-NMR and IR spectroscopy, and mass-spectrometry. Full article
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Scheme 1

Short Note
(E)-1-(5-Methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethan-1-one Oxime
Molbank 2023, 2023(1), M1593; https://doi.org/10.3390/M1593 - 21 Feb 2023
Viewed by 393
Abstract
The reaction of 1-(5-methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethan-1-one (1) with excess hydroxylamine hydrochloride (2 mole equivalents) in dry ethanol afforded (E)-1-(5-methyl-1-(4-nitrophenyl)-1H-1,2,3-triazol-4-yl)ethan-1-one oxime (2) in 86% yield. The structure of the new heterocycle 2 was confirmed using nuclear magnetic resonance spectroscopy, single crystal X-ray and elemental analysis. Full article
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Short Note
Triethylammonium 2-(3-Hydroxy-2-oxoindolin-3-yl)-5,5-dimethyl-3-oxocyclohex-1-en-1-olate
Molbank 2023, 2023(1), M1589; https://doi.org/10.3390/M1589 - 15 Feb 2023
Viewed by 450
Abstract
In recent years, the application of privileged structures has become a powerful approach in the discovery of new biologically active molecules. Ion pairing is a strategy used to enhance the permeation of ionized topical drugs. A convenient and efficient method for the synthesis [...] Read more.
In recent years, the application of privileged structures has become a powerful approach in the discovery of new biologically active molecules. Ion pairing is a strategy used to enhance the permeation of ionized topical drugs. A convenient and efficient method for the synthesis of triethylammonium 2-(3-hydroxy-2-oxoindolin-3-yl)-5,5-dimethyl-3-oxocyclohex-1-en-1-olate has been developed. The presented protocol includes an aldol reaction and the formation of an ammonium salt. Triethylamine is both a reactant and a catalyst in the process. The structure of the synthesized title compound has been established by 1H, 13C-NMR and IR spectroscopy, mass spectrometry, and elemental analysis. Full article
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Short Note
4-Benzoyl-2-(4-bromophenyl)-1-(4-methoxyphenyl)-1,2-dihydropyrimidino[4,3-c][1,4]benzoxazine-3,5-dione
Molbank 2023, 2023(1), M1583; https://doi.org/10.3390/M1583 - 08 Feb 2023
Viewed by 388
Abstract
The reaction of 3-benzoylpyrrolo[2,1-c][1,4]benzoxazin-1,2,4-trione with N-(4-bromophenyl)-1-(4-methoxyphenyl)methanimine under thermolytical conditions afforded 4-benzoyl-2-(4-bromophenyl)-1-(4-methoxyphenyl)-1,2-dihydropyrimidino[4,3-c][1,4]benzoxazine-3,5-dione in a good yield. The reaction proceeded via in situ generation of a reactive intermediate, acyl(imidoyl)ketene. The compound was fully characterized. Full article
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Short Note
(Z)-3-(Dicyanomethylene)-4-((5-fluoro-3,3-dimethyl-1-(3-phenylpropyl)-3H-indol-1-ium-2-yl) methylene)-2-(((E)-5-fluoro-3,3-dimethyl-1-(3-phenylpropyl)indolin-2-ylidene)methyl) cyclobut-1-en-1-olate
Molbank 2023, 2023(1), M1576; https://doi.org/10.3390/M1576 - 03 Feb 2023
Viewed by 457
Abstract
Recent literature on this topic highlights the significance of adding malononitrile moiety and halogen substituents to the squaraine scaffold to create redshifted fluorophores into the near-infrared optical region. Herein, a redshifted hydrophobic squaraine dye is synthesized via a three-step pathway. The reported dye [...] Read more.
Recent literature on this topic highlights the significance of adding malononitrile moiety and halogen substituents to the squaraine scaffold to create redshifted fluorophores into the near-infrared optical region. Herein, a redshifted hydrophobic squaraine dye is synthesized via a three-step pathway. The reported dye is characterized by spectroscopic techniques, such as 1H NMR, 19F NMR, 13C NMR, and high-resolution mass spectroscopy. Optical properties are also reported using absorbance and fluorescence studies. The hydrophobicity of the dye was studied with absorbance and fluorescence spectroscopy in water–methanol mixtures and showed J-aggregates as the water concentration increased. Density functional theory calculations were conducted to assess its electron delocalization as well as observe the three-dimensional geometry of the dye as a result of the dicyanomethylene modification and the two bulky phenyl groups. Full article
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Short Note
6-Chloro-3-nitro-2-[(phenylsulfonyl)methyl]imidazo[1,2-b]pyridazine
Molbank 2023, 2023(1), M1573; https://doi.org/10.3390/M1573 - 01 Feb 2023
Viewed by 466
Abstract
As part of our ongoing scaffold-hopping work on an antikinetoplastid 3-nitroimidazo[1,2-a]pyridine scaffold, we explored 3-nitroimidazo[1,2-b]pyridazine as a potential new antikinetoplastid series. Using conditions previously described by our lab, we obtained 6-chloro-3-nitro-2-[(phenylsulfonyl)methyl]imidazo[1,2-b]pyridazine with 54% yield. In vitro activity [...] Read more.
As part of our ongoing scaffold-hopping work on an antikinetoplastid 3-nitroimidazo[1,2-a]pyridine scaffold, we explored 3-nitroimidazo[1,2-b]pyridazine as a potential new antikinetoplastid series. Using conditions previously described by our lab, we obtained 6-chloro-3-nitro-2-[(phenylsulfonyl)methyl]imidazo[1,2-b]pyridazine with 54% yield. In vitro activity of this compound was evaluated against both the promastigote form of Leishmania donovani, the axenic amastigote form of Leishmania infantum and the trypomastigote blood stream form of Trypanosomabrucei brucei, and its influence on cell viability was assessed on the HepG2 cell line. However, despite good activity against the trypomastigote blood stream form of T. b. brucei (EC50 = 0.38 µM), it showed poor solubility in both HepG2 (CC50 > 7.8 µM) and L. infantum axenic amastigotes (EC50 > 1.6 µM) culture media, associated with a loss of activity against the promastigote form of L. infantum (EC50 > 15.6 µM). Full article
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Communication
(3-(1H-Indol-3-yl)-2-(7,8,12,13-tetraoxa-10-azaspiro[5.7]tridecan-10-yl)propanoic acid) with Cytotoxic Activity
Molbank 2023, 2023(1), M1572; https://doi.org/10.3390/M1572 - 01 Feb 2023
Viewed by 419
Abstract
An efficient method for the synthesis of 3-(1H-indol-3-yl)-2-(7,8,12,13-tetraoxa-10-azaspiro[5.7]tridecan-10-yl)propanoic acid) via condensation of 7,8,10,12,13-pentaoxaspiro[5.7]tridecane with tryptophan under the action of a catalyst based on Sm(NO3)3·6H2O has been developed. A high cytotoxic activity of eight-membered azadiperoxide against [...] Read more.
An efficient method for the synthesis of 3-(1H-indol-3-yl)-2-(7,8,12,13-tetraoxa-10-azaspiro[5.7]tridecan-10-yl)propanoic acid) via condensation of 7,8,10,12,13-pentaoxaspiro[5.7]tridecane with tryptophan under the action of a catalyst based on Sm(NO3)3·6H2O has been developed. A high cytotoxic activity of eight-membered azadiperoxide against tumor cells Jurkat, K562, U937, and HL60 was established. Additionally, this compound is an inducer of apoptosis and affects the cell cycle. Full article
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Short Note
2-{9-(10-Bromoanthracenyl)}-1,3-dihydro-1H-[d]-1,3,2-benzodiazaborole
Molbank 2023, 2023(1), M1569; https://doi.org/10.3390/M1569 - 27 Jan 2023
Viewed by 511
Abstract
In this paper, a synthesis and characterization of a novel three coordinate 2-{9-(10-Bromoanthracenyl)}-1,3-dihydro-1H-[d]-1,3,2-benzodiazaborole from a cyclo-condensation reaction of o-phenylenediamine and 10-bromoanthracene-9-boronic acid is described. The desired product was obtained in 0.343 g (92% yields) with its structure characterized [...] Read more.
In this paper, a synthesis and characterization of a novel three coordinate 2-{9-(10-Bromoanthracenyl)}-1,3-dihydro-1H-[d]-1,3,2-benzodiazaborole from a cyclo-condensation reaction of o-phenylenediamine and 10-bromoanthracene-9-boronic acid is described. The desired product was obtained in 0.343 g (92% yields) with its structure characterized by 1H, 11B, 13C NMR, HRMS and FT-IR. Full article
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Scheme 1

Communication
Synthesis of Pentacycloundecane (PCUD) Based Spiro-Pyrano-Cage Framework via Ring-Closing Metathesis
Molbank 2023, 2023(1), M1567; https://doi.org/10.3390/M1567 - 23 Jan 2023
Viewed by 660
Abstract
Here, we demonstrate a short synthetic route to pyrano cage systems containing pentacycloundecane units by employing ring-closing metathesis (RCM) as a key step. These cage systems were constructed starting with readily available starting materials by adopting atomic economic processes such as cycloadditions (Diels-Alder [...] Read more.
Here, we demonstrate a short synthetic route to pyrano cage systems containing pentacycloundecane units by employing ring-closing metathesis (RCM) as a key step. These cage systems were constructed starting with readily available starting materials by adopting atomic economic processes such as cycloadditions (Diels-Alder reaction and [2+2] cycloaddition), Grignard addition, and olefin metathesis. The key building block, such as hexacyclic cage dione, was prepared from 1,4-naphthoquinone derivative and freshly cracked 1,3-cyclopentadiene. Some of these heterocyclic motifs are useful in biological chemistry and valuable as key synthons for high-energy-density materials. Full article
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Communication
Synthesis of Bis(1,2,3-triazolyl)alkanes in Superbasic and Solvent-Free Conditions
Molbank 2023, 2023(1), M1551; https://doi.org/10.3390/M1551 - 13 Jan 2023
Viewed by 637
Abstract
Nucleophilic substitution reactions between 1,2,3-triazole and dibromomethane or 1,2-dirbomoethane in a superbasic medium potassium hydroxide–dimethyl sulfoxide gave mixtures of the isomeric bis(1,2,3-triazolyl)alkanes, in which (1,2,3-triazol-1-yl)(1,2,3-triazol-2-yl)alkanes and bis(1,2,3-triazol-2-yl)alkanes were the dominating products, while bis(triazol-1-yl)alkanes were detected only in trace amounts. The same products could [...] Read more.
Nucleophilic substitution reactions between 1,2,3-triazole and dibromomethane or 1,2-dirbomoethane in a superbasic medium potassium hydroxide–dimethyl sulfoxide gave mixtures of the isomeric bis(1,2,3-triazolyl)alkanes, in which (1,2,3-triazol-1-yl)(1,2,3-triazol-2-yl)alkanes and bis(1,2,3-triazol-2-yl)alkanes were the dominating products, while bis(triazol-1-yl)alkanes were detected only in trace amounts. The same products could also be obtained under solvent-free conditions in a neat reaction mixture. The proposed methods are economically feasible, do not require using toxic solvents or catalysts, and make the (1,2,3-triazol-2-yl)-derivatives, inaccessible by alkyne-azide cycloaddition (click) reactions, readily available. Full article
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Short Note
2,4-Diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H-chromeno[2,3-b]pyridine-3-carbonitrile
Molbank 2023, 2023(1), M1541; https://doi.org/10.3390/M1541 - 09 Jan 2023
Viewed by 573
Abstract
5H-Chromeno[2,3-b]pyridines are important compounds with industrial, biological, and medicinal properties. In this short note, the multicomponent reaction of salicylaldehyde, malononitrile dimer, and 2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one in dimethyl sulfoxide at ambient temperature was investigated to give 2,4-diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H [...] Read more.
5H-Chromeno[2,3-b]pyridines are important compounds with industrial, biological, and medicinal properties. In this short note, the multicomponent reaction of salicylaldehyde, malononitrile dimer, and 2-phenyl-5-(trifluoromethyl)-2,4-dihydro-3H-pyrazol-3-one in dimethyl sulfoxide at ambient temperature was investigated to give 2,4-diamino-5-(5-hydroxy-1-phenyl-3-(trifluoromethyl)-1H-pyrazol-4-yl)-5H-chromeno[2,3-b]pyridine-3-carbonitrile with good yield. The structure of the previously unknown chromeno[2,3-b]pyridine derivative was confirmed by elemental analysis, mass, nuclear magnetic resonance, and infrared spectroscopy data. The ADME (absorption, distribution, metabolism, and excretion) properties were also assessed. Full article
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2022

Jump to: 2023, 2021, 2020, 2019

Short Note
2-[2-(Diphenylphosphoryl)phenyl]-1H-perimidine
Molbank 2023, 2023(1), M1537; https://doi.org/10.3390/M1537 - 29 Dec 2022
Viewed by 735
Abstract
In this paper, we report the crystal structure of 2-[2-(diphenylphosphoryl)phenyl]-1H-perimidine (L1) obtained from the ring closure reaction of 1,8-diaminonaphthalene and 2-(diphenylphosphino)benzaldehyde, followed by the dehydrogenation reaction with sodium metabisulfite (Na2S2O5). L1 was characterised using 1H, 13 [...] Read more.
In this paper, we report the crystal structure of 2-[2-(diphenylphosphoryl)phenyl]-1H-perimidine (L1) obtained from the ring closure reaction of 1,8-diaminonaphthalene and 2-(diphenylphosphino)benzaldehyde, followed by the dehydrogenation reaction with sodium metabisulfite (Na2S2O5). L1 was characterised using 1H, 13C & 31P NMR, FT-IR and X-ray single structure analyses. Full article
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Communication
1-(4-{[3,5-bis({[3,5-Dimethyl-4-(4-methyl-3,5-dioxo-1,2,4-triazolidin-1-yl)-phenoxy]methyl})phenyl]methoxy}-2,6-dimethyl-phenyl)-4-methyl-1,2,4-triazolidine-3,5-dione
Molbank 2023, 2023(1), M1535; https://doi.org/10.3390/M1535 - 27 Dec 2022
Viewed by 552
Abstract
Appropriately substituted N-centered urazolyl radicals are capable of generating interesting cage-like structures upon forming N-N bonds. The radicals are generated by the oxidation of the corresponding NH urazole precursors. We synthesized a triurazole precursor that we hoped would dimerize through the formation of [...] Read more.
Appropriately substituted N-centered urazolyl radicals are capable of generating interesting cage-like structures upon forming N-N bonds. The radicals are generated by the oxidation of the corresponding NH urazole precursors. We synthesized a triurazole precursor that we hoped would dimerize through the formation of three N-N bonds to afford a large molecular cage. Unfortunately, the attempts at the oxidation of the urazoles to form urazolyl radicals instead only lead to random oligomerization, forming plastic-like materials rather than the desired cages. Full article
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Short Note
1-[2-(1H-Pyrrole-2-carbonyl)phenyl]-3-(4-methoxyphenyl)urea
Molbank 2023, 2023(1), M1531; https://doi.org/10.3390/M1531 - 22 Dec 2022
Viewed by 833
Abstract
For the synthesis of 1-(2-(1H-pyrrole-2-carbonyl)phenyl)-3-(4-methoxyphenyl)urea, the final product, two different methods were used, in one or two steps, from (2-aminophenyl)(1H-pyrrol-2-yl)methanone. The one-step synthesis entailed a carbonylation reaction with 1/3 equivalent of triphosgene in the presence of two equivalents of [...] Read more.
For the synthesis of 1-(2-(1H-pyrrole-2-carbonyl)phenyl)-3-(4-methoxyphenyl)urea, the final product, two different methods were used, in one or two steps, from (2-aminophenyl)(1H-pyrrol-2-yl)methanone. The one-step synthesis entailed a carbonylation reaction with 1/3 equivalent of triphosgene in the presence of two equivalents of trimethylamine, followed by the addition of 4-methoxyaniline to the in situ generated aryl isocyanate. The two-step synthesis required first the preparation of phenyl(2-(1H-pyrrole-2-carbonyl)phenyl)carbamate and then a substitution reaction by 4-methoxyaniline. The first method produced the final product in 72% yield, which was the best yield. The structure of the final product was confirmed by FTIR, UV-VIS, 1H and 13C NMR spectroscopy and high resolution mass spectrometry. Full article
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Short Note
2-Benzyl-3-morpholino-7-(thiophen-2-yl)-6-(thiophen-2-ylmethyl)-6,7-dihydro-5H-pyrrolo[3,4-b]pyridin-5-one
Molbank 2022, 2022(4), M1503; https://doi.org/10.3390/M1503 - 23 Nov 2022
Viewed by 552
Abstract
The new polyheterocyclic compound 2-benzyl-3-morpholino-7-(thiophen-2-yl)-6-(thiophen-2-ylmethyl)-6,7-dihydro-5H-pyrrolo[3,4-b]pyridin-5-one (1) was synthesized via a one-pot process involving an Ugi-Zhu three-component reaction coupled to a cascade aza-Diels-Alder cycloaddition/N-acylation/decarboxylation/dehydration process, using toluene as the solvent, ytterbium (III) triflate as the [...] Read more.
The new polyheterocyclic compound 2-benzyl-3-morpholino-7-(thiophen-2-yl)-6-(thiophen-2-ylmethyl)-6,7-dihydro-5H-pyrrolo[3,4-b]pyridin-5-one (1) was synthesized via a one-pot process involving an Ugi-Zhu three-component reaction coupled to a cascade aza-Diels-Alder cycloaddition/N-acylation/decarboxylation/dehydration process, using toluene as the solvent, ytterbium (III) triflate as the Lewis acid catalyst, and microwave-dielectric heating to increase the overall yield by up to 73%, while decreasing the reaction time to less than one hour. Product 1 was fully characterized by its physicochemical properties and using spectroscopic techniques (IR, HRMS and NMR). Full article
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Short Note
4-Methyl-7-((2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethyl)thio)-coumarin
Molbank 2022, 2022(4), M1491; https://doi.org/10.3390/M1491 - 12 Nov 2022
Viewed by 908
Abstract
The novel compound 4-methyl-7-((2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethyl)thio)-coumarin is obtained in good yield via a two-step protocol; that is, initial synthesis of the reagent 2-((2-chloroethyl)thio)-5-methyl-1,3,4-thiadiazole followed by alkylation of 7-mercapto-4-methylcoumarin. The product’s structure is assigned by 1D and 2D NMR experiments and is confirmed by single-crystal XRD. [...] Read more.
The novel compound 4-methyl-7-((2-((5-methyl-1,3,4-thiadiazol-2-yl)thio)ethyl)thio)-coumarin is obtained in good yield via a two-step protocol; that is, initial synthesis of the reagent 2-((2-chloroethyl)thio)-5-methyl-1,3,4-thiadiazole followed by alkylation of 7-mercapto-4-methylcoumarin. The product’s structure is assigned by 1D and 2D NMR experiments and is confirmed by single-crystal XRD. Full article
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Short Note
5-Chloro-6-oxo-6H-xantheno[4,3-d]thiazole-2-carbonitrile
Molbank 2022, 2022(4), M1489; https://doi.org/10.3390/M1489 - 10 Nov 2022
Viewed by 780
Abstract
Xanthones and benzothiazoles are important classes of heterocyclic compounds with versatile biological activities. Herein, we describe a straightforward and scalable synthesis of 5-chloro-6-oxo-6H-xantheno[4,3-d]thiazole-2-carbonitrile, a thiazole-fused xanthone, via a six-step approach, using Appel’s salt for the synthesis of the thiazole [...] Read more.
Xanthones and benzothiazoles are important classes of heterocyclic compounds with versatile biological activities. Herein, we describe a straightforward and scalable synthesis of 5-chloro-6-oxo-6H-xantheno[4,3-d]thiazole-2-carbonitrile, a thiazole-fused xanthone, via a six-step approach, using Appel’s salt for the synthesis of the thiazole ring. The thiazole-fused xanthone was fully characterized employing 1H and 13C NMR spectra, using direct and long-range heteronuclear correlation experiments (HMBC and HMQC). Full article
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Communication
Synthesis and Characterization of 3-Methyl-1-(4-(trifluoromethyl)phenyl)indeno [1,2-c]pyrazol-4(1H)-one
Molbank 2022, 2022(4), M1483; https://doi.org/10.3390/M1483 - 07 Nov 2022
Viewed by 974
Abstract
Pyrazoles have potential applications in the agrochemical and medicinal chemistry industries as pesticides, anti-inflammatory medications, and antitumor drugs. Fluorinated fused-ring pyrazoles may also possess medicinally useful properties. Herein, we report the acid-catalyzed synthesis of a new tricyclic, trifluoromethylated indenopyrazole, 3-methyl-1-(4-(trifluoromethyl)phenyl)indeno[1,2-c]pyrazol-4(1H)-one, from [...] Read more.
Pyrazoles have potential applications in the agrochemical and medicinal chemistry industries as pesticides, anti-inflammatory medications, and antitumor drugs. Fluorinated fused-ring pyrazoles may also possess medicinally useful properties. Herein, we report the acid-catalyzed synthesis of a new tricyclic, trifluoromethylated indenopyrazole, 3-methyl-1-(4-(trifluoromethyl)phenyl)indeno[1,2-c]pyrazol-4(1H)-one, from 2-acetyl-1,3-indanedione and 4-trifluoromethylphenylhydrazine. This isomeric pyrazole was obtained in yields ranging from 4–24%. NMR spectroscopic characterization and elemental analysis support the structural assignment, identity, and purity of the product. Full article
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Short Note
Dimethyl 3,7-diamino-4,8-bis((2-methoxy-2-oxoethyl)thio)benzo[1,2-b:4,5-b’]dithiophene-2,6-dicarboxylate
Molbank 2022, 2022(4), M1474; https://doi.org/10.3390/M1474 - 27 Oct 2022
Viewed by 605
Abstract
The convenient and multigram synthesis of a linear benzo[b]dithiophene (BDT) structure is proposed (dimethyl 3,7-diamino-4,8-bis((2-methoxy-2-oxoethyl)thio)benzo[1,2-b:4,5-b’]dithiophene-2,6-dicarboxylate). The starting materials are commercially available 2,3,5,6-tetrachloroterephthalonitrile and methyl 2-mercaptoacetate, which undergo aromatic substitution, followed by a cyclization reaction in basic conditions [...] Read more.
The convenient and multigram synthesis of a linear benzo[b]dithiophene (BDT) structure is proposed (dimethyl 3,7-diamino-4,8-bis((2-methoxy-2-oxoethyl)thio)benzo[1,2-b:4,5-b’]dithiophene-2,6-dicarboxylate). The starting materials are commercially available 2,3,5,6-tetrachloroterephthalonitrile and methyl 2-mercaptoacetate, which undergo aromatic substitution, followed by a cyclization reaction in basic conditions to form suitable BDT for potential optoelectronic applications. Full article
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1-Phenyl-3-tosyl-1H-pyrrole
Molbank 2022, 2022(4), M1471; https://doi.org/10.3390/M1471 - 26 Oct 2022
Viewed by 632
Abstract
1-Phenyl-3-tosyl-1H-pyrrole was prepared, in moderate yield, by the electrophilic aromatic substitution of 1-phenyl-1H-pyrrole with tosyl chloride in the presence of excess zinc oxide under solvent-free conditions. A minor product was its isomer, 1-phenyl-2-tosyl-1H-pyrrole. Full article
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Scheme 1

Short Note
3-Methyl 5-{3-[(4-Methylbenzenesulfonyl)oxy]propyl} 4-(2,3-Dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate
Molbank 2022, 2022(4), M1460; https://doi.org/10.3390/M1460 - 09 Oct 2022
Viewed by 777
Abstract
The 1,4-dihydropyridine is a ubiquitous scaffold employed not only in medicinal chemistry but also in organic synthesis, given its ability to act as a hydrogen transfer reagent, thus emulating NAD(P)H reducing agents. In this work, we describe the synthesis of 3-methyl 5-{3-[(4-methylbenzenesulfonyl)oxy]propyl} 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate [...] Read more.
The 1,4-dihydropyridine is a ubiquitous scaffold employed not only in medicinal chemistry but also in organic synthesis, given its ability to act as a hydrogen transfer reagent, thus emulating NAD(P)H reducing agents. In this work, we describe the synthesis of 3-methyl 5-{3-[(4-methylbenzenesulfonyl)oxy]propyl} 4-(2,3-dichlorophenyl)-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate as scaffold, which enables downstream derivatization towards new 1,4-dihydropyridine molecules. Inspired by the literature, a new two-step synthesis was planned that involved: (i) synthesis of a silylated 1,4-dihydropyridine derivative and (ii) deprotection and tosylation in one step using tosyl fluoride. Full article
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Ferrocenyl-bis-(1-(4-benzyl-5-morpholinooxazol-2-yl)-N-(4-(trifluoromethyl)benzyl)methanamine)
Molbank 2022, 2022(3), M1444; https://doi.org/10.3390/M1444 - 13 Sep 2022
Viewed by 864
Abstract
The new bis-heterocyclic compound ferrocenyl-bis-(1-(4-benzyl-5-morpholinooxazol-2-yl)-N-(4-(trifluoromethyl)benzyl)methanamine) (1) was synthesized in 73% overall yield in 1.5 hours via a pseudo-repetitive Ugi-Zhu five-component reaction, starting from 1,1′-ferrocenedicarboxaldehyde, 4-(trifluoromethyl)benzylamine, and 2-isocyano-1-morpholino-3-phenylpropan-1-one, in 1:2.1:2.2 proportions, respectively, using scandium(III) triflate as a [...] Read more.
The new bis-heterocyclic compound ferrocenyl-bis-(1-(4-benzyl-5-morpholinooxazol-2-yl)-N-(4-(trifluoromethyl)benzyl)methanamine) (1) was synthesized in 73% overall yield in 1.5 hours via a pseudo-repetitive Ugi-Zhu five-component reaction, starting from 1,1′-ferrocenedicarboxaldehyde, 4-(trifluoromethyl)benzylamine, and 2-isocyano-1-morpholino-3-phenylpropan-1-one, in 1:2.1:2.2 proportions, respectively, using scandium(III) triflate as a Lewis-acid catalyst, microwaves as a heat source, and toluene as a solvent. The synthesized compound was characterized by 1D (1H, 13C, and 19F) and 2D (COSY, HSQC, and HMBC) NMR, HRMS, and FT-IR. Full article
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Short Note
1,1′-{[3,5-Bis((dodecyloxycarbonyl)-4-phenyl-1,4-dihydropyridine-2,6-diyl]bis(methylene)}bis[4-(anthracen-9-yl)pyridin-1-ium] Dibromide
Molbank 2022, 2022(3), M1438; https://doi.org/10.3390/M1438 - 02 Sep 2022
Viewed by 892
Abstract
A synthesis of a cationic moiety and fluorescent moieties containing amphiphilic 1,4-dihydropyridine (1,4-DHP) derivatives was performed starting with the Hantzsch-type cyclization of dodecyl acetoacetate, phenylaldehyde and ammonium acetate. Bromination of the 2,6-dimethyl groups of a parent 1,4-DHP compound, followed by nucleophilic substitution of [...] Read more.
A synthesis of a cationic moiety and fluorescent moieties containing amphiphilic 1,4-dihydropyridine (1,4-DHP) derivatives was performed starting with the Hantzsch-type cyclization of dodecyl acetoacetate, phenylaldehyde and ammonium acetate. Bromination of the 2,6-dimethyl groups of a parent 1,4-DHP compound, followed by nucleophilic substitution of bromine with 4-(anthracen-9-yl)pyridine, produced the desired 1,1′-{[3,5-bis((dodecyloxycarbonyl)-4-phenyl-1,4-dihydropyridine-2,6-diyl]bis(methylene)}bis[4-(anthracen-9-yl)pyridin-1-ium] dibromide. The obtained target compound was fully characterized by the IR, 1H NMR, 13C NMR and HRMS data. Studies of the self-assembling properties and characterization of the nanoparticles obtained by the ethanol injection method were performed using dynamic light scattering (DLS) measurements. DLS measurement data showed that 1,1′-{[3,5-bis((dodecyloxycarbonyl)-4-phenyl-1,4-dihydropyridine-2,6-diyl]bis(methylene)}bis[4-(anthracen-9-yl)pyridin-1-ium] dibromide produced liposomes that had average diameters of 200 nm when the samples were freshly prepared, and 140 nm after 7 days or 1 month storage. The PDI values of the samples were approximately 0.50 and their zeta-potential values were approximately 41 mV when the samples were freshly prepared, and 33 mV after storage. The obtained nanoparticles were stored at room temperature for one month and remained stable during that period. The mean molecular area of the cationic 1,4-DHP-anthracene hybrid 4 was 118 Å2, while the mean molecular area of the cationic 1,4-DHP 5 without anthracene substituents was only 83 Å2. The photoluminescence quantum yield (PLQY) value for the EtOH solution of the 1,4-DHP derivative 4 was 10.8%, but for the 1,4-DHP derivative 5 it was only 1.8%. These types of compounds could be used as synthetic lipids in the further development of prospective theranostic delivery systems. Full article
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3-(1-Cyclohexyl-2-(cyclohexylamino)-4-(4-ethoxyphenyl)-6-oxo-1,6-dihydropyrimidin-5-yl)-1-methylquinoxalin-2(1H)-one
Molbank 2022, 2022(3), M1421; https://doi.org/10.3390/M1421 - 05 Aug 2022
Viewed by 1001
Abstract
The reaction of 3-cyclohexyl-2-(cyclohexylimino)-6-(4-ethoxyphenyl)-5-(4-methyl-3-oxo-3,4-dihydroquinoxalin-2-yl)-2,3-dihydro-4H-1,3-oxazin-4-one with ammonium acetate afforded 3-(1-cyclohexyl-2-(cyclohexylamino)-4-(4-ethoxyphenyl)-6-oxo-1,6-dihydropyrimidin-5-yl)-1-methylquinoxalin-2(1H)-one in a good yield. The compound was fully characterized. Full article
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12H-Dibenzo[d,g][1,2,3]triselenocin-12-ol
Molbank 2022, 2022(3), M1418; https://doi.org/10.3390/M1418 - 01 Aug 2022
Viewed by 912
Abstract
Reaction of diphenylmethanol (4) with n-butyllithium and subsequent treatment with selenium resulted in 12H-dibenzo[d,g][1,2,3]triselenocin-12-ol (5) comprising a novel heterocyclic ring system. The title compound 5 was analyzed by 1H-NMR, 13C-NMR [...] Read more.
Reaction of diphenylmethanol (4) with n-butyllithium and subsequent treatment with selenium resulted in 12H-dibenzo[d,g][1,2,3]triselenocin-12-ol (5) comprising a novel heterocyclic ring system. The title compound 5 was analyzed by 1H-NMR, 13C-NMR and HPLC. Additionally, the structure of 5 was confirmed by single crystal X-ray diffraction. Full article
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3-Amino-4-(diphenylamino)-1H-2-benzopyran-1-one
Molbank 2022, 2022(3), M1408; https://doi.org/10.3390/M1408 - 14 Jul 2022
Viewed by 965
Abstract
Various synthetic methodologies to obtain 3,4-diaminoisocumarin nucleus have been reported and described. However, mechanistic analysis based on experimental evidence is lacking. Herein, we report the synthesis of the novel 3-amino-4-(diphenylamino)-1H-2-benzopyran-1-one using a two-step methodology with a new mechanistic proposal to explain [...] Read more.
Various synthetic methodologies to obtain 3,4-diaminoisocumarin nucleus have been reported and described. However, mechanistic analysis based on experimental evidence is lacking. Herein, we report the synthesis of the novel 3-amino-4-(diphenylamino)-1H-2-benzopyran-1-one using a two-step methodology with a new mechanistic proposal to explain the formation of the latter based on previously reported precursors and the established conditions. This compound was afforded in 80% yield. Full article
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Communication
Unexpected Formation of 4-[(1-Carbamoyl-3-oxo-1,3-dihydro-2-benzofuran-1-yl)amino]benzoic Acid from 4-[(3-Amino-1-oxo-1H-2-benzopyran-4-yl)amino]benzoic Acid
Molbank 2022, 2022(3), M1407; https://doi.org/10.3390/M1407 - 12 Jul 2022
Viewed by 914
Abstract
With the aim of obtaining derivatives belonging to 2′,3′-diphenyl-3H-spiro[[2]benzofuran-1,4′-imidazole]-3,5′(3′H)-dione nucleus, we synthesized 4-[(3-amino-1-oxo-1H-2-benzopyran-4-yl)amino]benzoic acid (a 3,4-diaminoisocoumarine derivative), a known precursor of 4-[(1-carbamoyl-3-oxo-1,3-dihydro-2-benzofuran-1-yl)amino]benzoic acid (a phthalide–carboxamide-bearing system) by a novel methodology that we report here. The reaction conditions [...] Read more.
With the aim of obtaining derivatives belonging to 2′,3′-diphenyl-3H-spiro[[2]benzofuran-1,4′-imidazole]-3,5′(3′H)-dione nucleus, we synthesized 4-[(3-amino-1-oxo-1H-2-benzopyran-4-yl)amino]benzoic acid (a 3,4-diaminoisocoumarine derivative), a known precursor of 4-[(1-carbamoyl-3-oxo-1,3-dihydro-2-benzofuran-1-yl)amino]benzoic acid (a phthalide–carboxamide-bearing system) by a novel methodology that we report here. The reaction conditions were optimized to afford the latter in 62% yield. Full article
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Communication
Synthesis and Evaluation of Self-Assembling Properties of 3-(3,5-Difluoro-3,5-bis((alkoxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium Iodides
Molbank 2022, 2022(3), M1402; https://doi.org/10.3390/M1402 - 06 Jul 2022
Viewed by 1009
Abstract
A synthesis of 3-(3,5-difluoro-3,5-bis((alkoxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium iodides with ethyl or nonyl ester groups at positions 3 and 5 was performed. Treatment of the corresponding 2’,6’-dimethyl-1’,4’-dihydro-[3,4’-bipyridine]-3’,5’-dicarboxylates with Selectfluor® followed by quaternization of pyridine moiety in the obtained dialkyl 2,4-diacetyl-2,4-difluoro-3-(pyridin-3-yl)pentanedioates with methyl iodide gave the desired [...] Read more.
A synthesis of 3-(3,5-difluoro-3,5-bis((alkoxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium iodides with ethyl or nonyl ester groups at positions 3 and 5 was performed. Treatment of the corresponding 2’,6’-dimethyl-1’,4’-dihydro-[3,4’-bipyridine]-3’,5’-dicarboxylates with Selectfluor® followed by quaternization of pyridine moiety in the obtained dialkyl 2,4-diacetyl-2,4-difluoro-3-(pyridin-3-yl)pentanedioates with methyl iodide gave the desired 3-(3,5-difluoro-3,5-bis((alkoxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium iodides. This type of compound would be useful as synthetic lipids for further development of the delivery systems. The obtained target compounds were fully characterized by 1H NMR, 19F NMR, 13C NMR, HRMS, IR and UV data. The estimation of self-assembling properties and characterization of the nanoparticles obtained by ethanol solution injection in an aqueous media were performed by dynamic light scattering (DLS) measurements. DLS measurement data showed that 3-(3,5-difluoro-3,5-bis((nonyloxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium iodide created liposomes with the average diameter of 300–400 nm and polydispersity index (PDI) value around 0.30–0.40, while 3-(3,5-difluoro-3,5-bis((ethyloxy)carbonyl)-2,6-dioxoheptan-4-yl)-1-methylpyridin-1-ium iodide formed a heterogeneous sample with PDI value 1, which was not prospective for delivery system development. Full article
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Communication
Styryl Hemicyanine Dye (E)-3-Methyl-2-(4-thiomorpholinostyryl)benzo[d]thiazol-3-ium Iodide for Nucleic Acids and Cell Nucleoli Visualization
Molbank 2022, 2022(2), M1392; https://doi.org/10.3390/M1392 - 20 Jun 2022
Cited by 1 | Viewed by 1182
Abstract
(E)-3-Methyl-2-(4-thiomorpholinostyryl)benzo[d]thiazol-3-ium iodide 1 was prepared by a convenient and reliable reaction procedure. The slight molar excess of the starting benzaldehyde and the mixture of ethanol: ethyl acetate in the ratio 3:1 as a solvent afforded a pure reaction product. The photophysical [...] Read more.
(E)-3-Methyl-2-(4-thiomorpholinostyryl)benzo[d]thiazol-3-ium iodide 1 was prepared by a convenient and reliable reaction procedure. The slight molar excess of the starting benzaldehyde and the mixture of ethanol: ethyl acetate in the ratio 3:1 as a solvent afforded a pure reaction product. The photophysical properties of the dye in a TE buffer in the absence and presence of double-stranded DNA (dsDNA) were elucidated. The low intrinsic fluorescence of 1 in TE buffer is followed by an increase in the fluorescence after dsDNA binding. The dye is nontoxic for stem cells from apical papilla and the most concentrated fluorescence is detected in the cell nucleoli. Full article
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Communication
Synthesis, Crystal Structure and Anti-Leukemic Activity of 1,3-Dihydro-1-{1-[4-(4-phenylpyrrolo[1,2-a]quinoxalin-3-yl)benzyl]piperidin-4-yl}-2H-benzimidazol-2-one
Molbank 2022, 2022(1), M1333; https://doi.org/10.3390/M1333 - 09 Feb 2022
Viewed by 1329
Abstract
1,3-Dihydro-1-{1-[4-(4-phenylpyrrolo[1,2-a]quinoxalin-3-yl)benzyl]piperidin-4-yl}-2H-benzimidazol-2-one has been synthesized through a multi-step pathway starting from commercially available 2-nitroaniline. A structure characterization of this new substituted pyrrolo[1,2-a]quinoxaline compound was achieved by using FT-IR, 1H-NMR, 13C-NMR, X-Ray and HRMS spectral analysis. This [...] Read more.
1,3-Dihydro-1-{1-[4-(4-phenylpyrrolo[1,2-a]quinoxalin-3-yl)benzyl]piperidin-4-yl}-2H-benzimidazol-2-one has been synthesized through a multi-step pathway starting from commercially available 2-nitroaniline. A structure characterization of this new substituted pyrrolo[1,2-a]quinoxaline compound was achieved by using FT-IR, 1H-NMR, 13C-NMR, X-Ray and HRMS spectral analysis. This new pyrroloquinoxaline derivative shows an interesting cytotoxic potential against several human leukemia cell lines (HL60, K562 and U937 cells). Full article
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2021

Jump to: 2023, 2022, 2020, 2019

Communication
CF3-Bis-TEMPO-Vis: New Visible Light Active Bis-Benzimidazolequinone Alkoxyamine
Molbank 2021, 2021(4), M1300; https://doi.org/10.3390/M1300 - 26 Nov 2021
Viewed by 1668
Abstract
Alkoxyamines of TEMPO usually dissociate thermally at >100 °C; however, room temperature homolysis, activated by visible light, occurs with benzimidazolequinone derivatives. 1,1’-Dimethyl-2,2’-bis{[(2,2,6,6-tetramethylpiperidin-1-yl)oxy]methyl}-6-(trifluoromethyl)-1H,1’H-[5,5’-bibenzimidazole]-4,4’,7,7’-tetrone (CF3-Bis-TEMPO-Vis) is prepared in a 59% yield through NBS/H2SO4 oxidative [...] Read more.
Alkoxyamines of TEMPO usually dissociate thermally at >100 °C; however, room temperature homolysis, activated by visible light, occurs with benzimidazolequinone derivatives. 1,1’-Dimethyl-2,2’-bis{[(2,2,6,6-tetramethylpiperidin-1-yl)oxy]methyl}-6-(trifluoromethyl)-1H,1’H-[5,5’-bibenzimidazole]-4,4’,7,7’-tetrone (CF3-Bis-TEMPO-Vis) is prepared in a 59% yield through NBS/H2SO4 oxidative demethylations of the dimethoxybenzimidazole-benzimidazolequinone precursor with aqueous work up. The alternative basic work up in air gave the epoxide derivative of CF3-Bis-TEMPO-Vis. Unlike the latter CF3-epoxide, both alkoxyamine residues are labile under green light (470–600 nm), and the rate of TEMPO release is three times slower than Bis-TEMPO-Vis. Full article
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Communication
Regioselective Synthesis of 4-Bromo-3-formyl-N-phenyl-5-propylthiophene-2-carboxamide
Molbank 2021, 2021(4), M1296; https://doi.org/10.3390/M1296 - 16 Nov 2021
Cited by 1 | Viewed by 1643
Abstract
We synthesized 4-bromo-3-formyl-N-phenyl-5-propylthiophene-2-carboxamide by using three successive direct lithiations and a bromination reaction starting from thiophene. All these lithiation reactions were carried out at −78 °C to RT over a period of 1 to 24 h based on the reactivity of [...] Read more.
We synthesized 4-bromo-3-formyl-N-phenyl-5-propylthiophene-2-carboxamide by using three successive direct lithiations and a bromination reaction starting from thiophene. All these lithiation reactions were carried out at −78 °C to RT over a period of 1 to 24 h based on the reactivity of electrophile. This is a four-step protocol starting from thiophene with an overall yield of 47%. Full article
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Short Note
4,7-Bis(1,2,3,4,4a,9a-Hexahydro-9H-carbazol-9-yl)-[1,2,5]oxadiazolo[3,4-d]pyridazine
Molbank 2021, 2021(4), M1295; https://doi.org/10.3390/M1295 - 05 Nov 2021
Cited by 1 | Viewed by 1507
Abstract
New donor-acceptor-donor (D-A-D)-type structures are widely used to design effective organic light-emitting diodes (OLEDs). In this communication, 4,7-bis(1,2,3,4,4a,9a-hexahydro-9H-carbazol-9-yl)-[1,2,5]oxadiazolo[3,4-d]pyridazine was obtained in a 65% yield by the treatment of 4,7-dichloro[1,2,5]oxadiazolo[3,4-d]pyridazine 1-oxide with 2,3,4,4a,9,9a-hexahydro-1H-carbazole. The structure of [...] Read more.
New donor-acceptor-donor (D-A-D)-type structures are widely used to design effective organic light-emitting diodes (OLEDs). In this communication, 4,7-bis(1,2,3,4,4a,9a-hexahydro-9H-carbazol-9-yl)-[1,2,5]oxadiazolo[3,4-d]pyridazine was obtained in a 65% yield by the treatment of 4,7-dichloro[1,2,5]oxadiazolo[3,4-d]pyridazine 1-oxide with 2,3,4,4a,9,9a-hexahydro-1H-carbazole. The structure of the newly synthesized compounds was established by means of an elemental analysis, 1H, 13C NMR, IR and UV spectroscopy, and HRMS and LR mass-spectrometry. Full article
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Short Note
6-(Chloromethyl)-N,1-dimethyl-1H-pyrazolo[3,4-d]pyrimidin-4-amine
Molbank 2021, 2021(4), M1294; https://doi.org/10.3390/M1294 - 01 Nov 2021
Cited by 1 | Viewed by 1555
Abstract
Functionally 4,6-disubstituted 1H-pyrazolo[3,4-d]pyrimidines are important compounds with various pharmacological activities. 1-Substituted 4-chloro-6-(chloromethyl)-1H-pyrazolo[3,4-d]pyrimidines are practically unexplored derivatives in this series. In this paper, it was shown that the nucleophilic substitution of 4-Chloro-6-(chloromethyl)-1-methyl-1H-pyrazolo[3,4-d]pyrimidine [...] Read more.
Functionally 4,6-disubstituted 1H-pyrazolo[3,4-d]pyrimidines are important compounds with various pharmacological activities. 1-Substituted 4-chloro-6-(chloromethyl)-1H-pyrazolo[3,4-d]pyrimidines are practically unexplored derivatives in this series. In this paper, it was shown that the nucleophilic substitution of 4-Chloro-6-(chloromethyl)-1-methyl-1H-pyrazolo[3,4-d]pyrimidine with methylamine produced selectively 4-substituted product, 6-(chloromethyl)-N,1-dimethyl-1H-pyrazolo[3,4-d]pyrimidin-4-amine. The structure of the synthesized compound was established by elemental analysis, high resolution mass-spectrometry, 1H, 13C-NMR, and IR spectroscopy, mass-spectrometry, and X-ray analysis. Full article
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Communication
Ambient-Temperature Synthesis of (E)-N-(3-(tert-Butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanimine
Molbank 2021, 2021(3), M1250; https://doi.org/10.3390/M1250 - 07 Jul 2021
Viewed by 1564
Abstract
We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 in methanol using magnesium sulfate as a drying agent. [...] Read more.
We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 in methanol using magnesium sulfate as a drying agent. The N-pyrazolyl imine 3 was full characterized by IR, 1D, and 2D NMR spectroscopy, mass spectrometry, and elemental analysis. Full article
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(2,3-Dihydro-1H-indol-5-ylmethyl)amine
Molbank 2021, 2021(3), M1248; https://doi.org/10.3390/M1248 - 05 Jul 2021
Viewed by 1432
Abstract
New (2,3-dihydro-1H-indol-5-ylmethyl)amine was synthesized from 2-((1-acetylindolin-5-yl)methyl)isoindoline-1,3-dione by simultaneous deprotection of phthalimide and acetyl groups. The structure of the newly synthesized compounds was established by elemental analysis, high resolution mass-spectrometry, 1H, 13C NMR and IR spectroscopy and mass-spectrometry. The resulting [...] Read more.
New (2,3-dihydro-1H-indol-5-ylmethyl)amine was synthesized from 2-((1-acetylindolin-5-yl)methyl)isoindoline-1,3-dione by simultaneous deprotection of phthalimide and acetyl groups. The structure of the newly synthesized compounds was established by elemental analysis, high resolution mass-spectrometry, 1H, 13C NMR and IR spectroscopy and mass-spectrometry. The resulting compound is a convenient intermediate for various disubstituted 1-(indolin-5-yl)methanamines, which may be of interest as substances with useful pharmacological properties. Full article
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Short Note
(E)-4-Oxo-3,4-dihydroquinazoline-2-carbaldehyde Oxime
Molbank 2021, 2021(2), M1233; https://doi.org/10.3390/M1233 - 11 Jun 2021
Viewed by 1481
Abstract
Reaction of 4-oxo-3,4-dihydroquinazoline-2-carbaldehyde with hydroxylamine hydrochloride (1.1 equiv) in the presence of K2CO3 (1 equiv) gave (E)-4-oxo-3,4-dihydroquinazoline-2-carbaldehyde oxime (8) in 58% yield. The compound was fully characterized and the conformation of the oxime was supported by single crystal x-ray diffractometry. Full article
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Short Note
3-(tert-Butyl)-N-(4-methoxybenzyl)-1-methyl-1H-pyrazol-5-amine
Molbank 2021, 2021(1), M1196; https://doi.org/10.3390/M1196 - 10 Mar 2021
Cited by 2 | Viewed by 1746
Abstract
We reported an efficient one-pot two-step synthesis of 3-(tert-butyl)-N-(4-methoxybenzyl)-1-methyl-1H-pyrazol-5-amine 3 in good yield by a solvent-free condensation/reduction reaction sequence starting from 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and p-methoxybenzaldehyde 2. The one-pot reductive amination proceeded [...] Read more.
We reported an efficient one-pot two-step synthesis of 3-(tert-butyl)-N-(4-methoxybenzyl)-1-methyl-1H-pyrazol-5-amine 3 in good yield by a solvent-free condensation/reduction reaction sequence starting from 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and p-methoxybenzaldehyde 2. The one-pot reductive amination proceeded by the formation in situ of the N-(5-pyrazolyl)imine 4 as key synthetic intermediate of other valuable pyrazole derivatives. This methodology is distinguished by its operational easiness, short reaction time, isolation and purification of the aldimine intermediate is not required. The structure of the synthesized N-heterocyclic amine 3 was fully characterized by FTIR-ATR, 1D and 2D NMR experiments, EIMS, and elemental analysis. Full article
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Communication
Synthesis of 1,5-Disubstituted Tetrazoles in Aqueous Micelles at Room Temperature
Molbank 2021, 2021(1), M1194; https://doi.org/10.3390/M1194 - 09 Mar 2021
Cited by 2 | Viewed by 1525
Abstract
The ongoing study is a Ugi-azide four-component reaction for the synthesis of 1,5-disubstituted tetrazole(1,5-DST), which involves an aldehyde, different amines, isocyanides, and as azide’s source the Trimethylsilylazide (TMSN3), in water as solvent using as catalyst the tetradecyltrimethylammonium bromide (TTAB) with a [...] Read more.
The ongoing study is a Ugi-azide four-component reaction for the synthesis of 1,5-disubstituted tetrazole(1,5-DST), which involves an aldehyde, different amines, isocyanides, and as azide’s source the Trimethylsilylazide (TMSN3), in water as solvent using as catalyst the tetradecyltrimethylammonium bromide (TTAB) with a load of (10% mole), which provides a hydrophobic micellar reaction site. This approach is a step toward a green chemistry reaction of 1,5 disubstituted tetrazole. A serie of 1, 5- disubstituted tetrazole was synthesized by engaging a large substrate scope, leading to yields between 43% and 56%, which are compared afterwards with those obtained with methanol as solvent. The results were confirmed by HRMS, IR, and 1D NMR experiments. Full article
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Ethyl 1-Butyl-2-(2-hydroxy-4-methoxyphenyl)-1H-benzo[d]imidazole-5-carboxylate
Molbank 2021, 2021(1), M1192; https://doi.org/10.3390/M1192 - 24 Feb 2021
Viewed by 1469
Abstract
Ethyl 4-(butylamino)-3-nitrobenzoate upon “one-pot” nitro-reductive cyclization using sodium dithionite and substituted aldehyde in dimethyl sulphoxide affords ethyl 1-butyl-2-(2-hydroxy-4-methoxyphenyl)-1H-benzo[d]imidazole-5-carboxylate in an 87% yield. The structural characterization was determined by Fourier-transfer infrared spectroscopy (FT-IR), Proton nuclear magnetic resonance (1H-NMR), [...] Read more.
Ethyl 4-(butylamino)-3-nitrobenzoate upon “one-pot” nitro-reductive cyclization using sodium dithionite and substituted aldehyde in dimethyl sulphoxide affords ethyl 1-butyl-2-(2-hydroxy-4-methoxyphenyl)-1H-benzo[d]imidazole-5-carboxylate in an 87% yield. The structural characterization was determined by Fourier-transfer infrared spectroscopy (FT-IR), Proton nuclear magnetic resonance (1H-NMR), Carbon-13 nuclear magnetic resonance (13C-NMR), mass spectrometry, Ultraviolet-visible(UV-Vis), photoluminescence (PL), thin-film solid emission spectra, cyclic voltammetry (CV) and thermogravimetric (TGA) analysis. Molecular electrostatic potential (MEP) was studied to determine the reactive sites of the molecule. Full article
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Short Note
2-Amino-5-chloro-1H-pyrrole-3,4-dicarbonitrile
Molbank 2021, 2021(1), M1191; https://doi.org/10.3390/M1191 - 13 Feb 2021
Cited by 1 | Viewed by 2127
Abstract
The reaction of tetracyanoethylene (TCNE) with HCl (g) in the presence of Sn (1 equiv) and AcOH resulted in 2-amino-5-chloro-1H-pyrrole-3,4-dicarbonitrile in a 74% yield. The compound was fully characterized. Full article
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Graphical abstract

Communication
Tetramethyl 1,1′-(2-[{4,5-bis(Methoxycarbonyl)-1H-1,2,3-triazol-1-yl}methyl]-2-[(4-methylphenyl)sulfonamido]propane-1,3-diyl)bis(1H-1,2,3-triazole-4,5-dicarboxylate)
Molbank 2021, 2021(1), M1186; https://doi.org/10.3390/M1186 - 31 Jan 2021
Cited by 1 | Viewed by 1775
Abstract
A new compound tetramethyl 1,1′-(2-[{4,5-bis(methoxycarbonyl)-1H-1,2,3-triazol-1-yl}methyl]-2-[(4-methylphenyl)sulfonamido]propane-1,3-diyl)bis(1H-1,2,3-triazole-4,5-dicarboxylate) (3) was prepared in two steps starting from 2-((4-methylphenyl)sulfonamido)-2-((tosyloxy)methyl)propane-1,3-diylbis(4-methylbenzenesulfonate) (1), with an overall yield of 74%. The key step being the copper-free Huisgen cycloaddition between N [...] Read more.
A new compound tetramethyl 1,1′-(2-[{4,5-bis(methoxycarbonyl)-1H-1,2,3-triazol-1-yl}methyl]-2-[(4-methylphenyl)sulfonamido]propane-1,3-diyl)bis(1H-1,2,3-triazole-4,5-dicarboxylate) (3) was prepared in two steps starting from 2-((4-methylphenyl)sulfonamido)-2-((tosyloxy)methyl)propane-1,3-diylbis(4-methylbenzenesulfonate) (1), with an overall yield of 74%. The key step being the copper-free Huisgen cycloaddition between N-(1,3-diazido-2-(azidomethyl)propan-2-yl)-4-methylbenzenesulfonamide (2) and commercially available dimethyl acetylenedicarboxylate. The chemical structure of compound 3 was determined by IR, 1D and 2D NMR experiments, and elemental analysis. Full article
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Short Note
N-(6-Chloro-3-nitropyridin-2-yl)-5-(1-methyl-1H-pyrazol-4-yl)isoquinolin-3-amine
Molbank 2021, 2021(1), M1181; https://doi.org/10.3390/M1181 - 18 Jan 2021
Cited by 1 | Viewed by 2373
Abstract
Here we describe the synthesis of N-(6-chloro-3-nitropyridin-2-yl)5-(1-methyl-1H-pyrazol-4-yl)isoquinolin-3-amine via a three-step procedure including a Buchwald–Hartwig arylamination with benzophenone imine and a highly regioselective nucleophilic aromatic substitution. The title compound was analyzed by nuclear magnetic resonance spectroscopy (1H, 13C, [...] Read more.
Here we describe the synthesis of N-(6-chloro-3-nitropyridin-2-yl)5-(1-methyl-1H-pyrazol-4-yl)isoquinolin-3-amine via a three-step procedure including a Buchwald–Hartwig arylamination with benzophenone imine and a highly regioselective nucleophilic aromatic substitution. The title compound was analyzed by nuclear magnetic resonance spectroscopy (1H, 13C, HSQC, HMBC, COSY, DEPT90 and NOESY), high resolution mass spectrometry (ESI-TOF-HRMS) and infrared spectroscopy (ATR-IR) and its structure was confirmed by single crystal X-ray diffraction. The inhibitory potency of the title compound was evaluated for selected kinases harboring a rare cysteine in the hinge region (MPS1, MAPKAPK2 and p70S6Kβ/S6K2). Full article
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(S)-1-(Ethoxycarbonyl)ethyl(2R,5S)-2,5-dimethyl-1,3-dioxolan-4-one-2-carboxylate
Molbank 2021, 2021(1), M1178; https://doi.org/10.3390/M1178 - 02 Jan 2021
Cited by 1 | Viewed by 1650
Abstract
The title compound was obtained in low yield in the condensation of ethyl pyruvate and lactic acid. Its structure is determined by NMR methods and x-ray diffraction and the mechanism for formation of this 1:2 adduct from the initial 1:1 adduct is considered. [...] Read more.
The title compound was obtained in low yield in the condensation of ethyl pyruvate and lactic acid. Its structure is determined by NMR methods and x-ray diffraction and the mechanism for formation of this 1:2 adduct from the initial 1:1 adduct is considered. Full article
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2020

Jump to: 2023, 2022, 2021, 2019

Short Note
Methyl (2E)-3-[3-Benzyl-2-(3-methoxy-3-oxoprop-1-yn-1-yl)-2-(1-naphthyl)imidazolidin-1-yl]acrylate
Molbank 2021, 2021(1), M1176; https://doi.org/10.3390/M1176 - 30 Dec 2020
Viewed by 1617
Abstract
Compounds with propargylamine moiety are useful synthetic precursors of several important classes of nitrogen-containing heterocycles. The title compound, methyl (2E)-3-[3-benzyl-2-(3-methoxy-3-oxoprop-1-yn-1-yl)-2-(1-naphthyl)imidazolidine-1-yl]acrylate, has been prepared by domino-reaction, employing easily available 1-benzyl-2-(1-naphthyl)-4,5-dihydro-1H-imidazole and methyl propiolate in a high 92% yield. The structure [...] Read more.
Compounds with propargylamine moiety are useful synthetic precursors of several important classes of nitrogen-containing heterocycles. The title compound, methyl (2E)-3-[3-benzyl-2-(3-methoxy-3-oxoprop-1-yn-1-yl)-2-(1-naphthyl)imidazolidine-1-yl]acrylate, has been prepared by domino-reaction, employing easily available 1-benzyl-2-(1-naphthyl)-4,5-dihydro-1H-imidazole and methyl propiolate in a high 92% yield. The structure of title compound was determined using 1H-NMR, 13C-NMR, UV, FT-IR and HRMS (High-Resolution Mass Spectrometry). Full article
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Short Note
4,4′-(Pyrrolo[3,2-b]pyrrole-1,4-diyl)dianiline
Molbank 2020, 2020(4), M1169; https://doi.org/10.3390/M1169 - 23 Nov 2020
Cited by 2 | Viewed by 1663
Abstract
4,4′-(Pyrrolo[3,2-b]pyrrole-1,4-diyl)dianiline was synthesized in one step from benzene-1,4-diamine and ethylene glycol with Pd/Al2O3 and ZnO. The title compound was characterized by means of NMR techniques and HRMS mass spectrometry. Full article
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Short Note
6-Nitro-7-tosylquinazolin-4(3H)-one
Molbank 2020, 2020(4), M1168; https://doi.org/10.3390/M1168 - 21 Nov 2020
Viewed by 2136
Abstract
Sulfones are important building blocks in the construction of biologically active molecules or functional materials. The sulfonyl functional group in sulfones is so versatile that it can act as either a nucleophile, an electrophile, or a radical in different organic reactions. Recently, quinazoline [...] Read more.
Sulfones are important building blocks in the construction of biologically active molecules or functional materials. The sulfonyl functional group in sulfones is so versatile that it can act as either a nucleophile, an electrophile, or a radical in different organic reactions. Recently, quinazoline sulfones have been used to build asymmetrical ether derivatives as inhibitors of signaling pathways governed by tyrosine kinases and the epidermal growth factor-receptor. In this paper, we report a facile synthesis of a novel quinazoline sulfone, 6-nitro-7-tosylquinazolin-4(3H)-one (III), using the modified protocol from 7-chloro-6-nitroquinazolin-4(3H)-one (I) and sodium p-toluenesulfinate (II). The structure of the title compound III was determined using mass-spectrometry, FT-IR, 1H-NMR, 13C-NMR, DEPT, HSQC (Heteronuclear single quantum coherence), HMBC (Heteronuclear Multiple Bond Correlation Spectroscopy) spectroscopies, and PXRD analysis. Full article
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Short Note
Ethyl (S)-2-Benzamido-5-[(4,6-dimethylpyrimidin-2-yl)amino]pentanoate
Molbank 2020, 2020(4), M1166; https://doi.org/10.3390/M1166 - 13 Nov 2020
Viewed by 1787
Abstract
Pyrimidines are compounds with a wide range of biological activities, and the synthesis of pyrimidine derivatives—useful in chemical and medicinal applications—is important in medicinal chemistry. This work shows the synthesis under microwave irradiation of the novel compound ethyl (S)-2-benzamido-5-[(4,6-dimethylpyrimidin-2-yl)amino]pentanoate (3 [...] Read more.
Pyrimidines are compounds with a wide range of biological activities, and the synthesis of pyrimidine derivatives—useful in chemical and medicinal applications—is important in medicinal chemistry. This work shows the synthesis under microwave irradiation of the novel compound ethyl (S)-2-benzamido-5-[(4,6-dimethylpyrimidin-2-yl)amino]pentanoate (3) from (S)-N-α-benzoyl-l-arginine ethyl ester hydrochloride (1) and acetylacetone (2). Compound 3 was easily purified, obtained in moderate yield (70%), and fully characterized by UV-Vis, FTIR-ATR spectroscopy, 1H-NMR, 13C-NMR, HRMS, and EI-MS. Full article
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Short Note
Sodium N-(3,5-Bis(ethoxycarbonyl)-2,6-dimethyl-1,4-dihydropyridine-4-carbonyl)-l-methioninate
Molbank 2020, 2020(3), M1148; https://doi.org/10.3390/M1148 - 14 Jul 2020
Viewed by 2320
Abstract
The development of the methods for amide bond formation is important for various uses in the laboratory and industrial applications. The compounds combined in their structures 1,4-dihydroisonicotinic acids and amino acids linked with an amide bond can be considered as “privileged structures” due [...] Read more.
The development of the methods for amide bond formation is important for various uses in the laboratory and industrial applications. The compounds combined in their structures 1,4-dihydroisonicotinic acids and amino acids linked with an amide bond can be considered as “privileged structures” due to their broad range of biological activities. Herein, the formation of amide bond between 1,4-dihydroisonicotinic acid and l-methionine is reported. The coupling of l-methionine with pentafluorophenyl active ester of 1,4-dihydroisonicotinic acid appears to be a convenient and effective method for amide bond formation. Sodium N-(3,5-bis(ethoxycarbonyl)-2,6-dimethyl-1,4-dihydropyridine-4-carbonyl)-l-methioninate has been successfully synthesized via a procedure where the key step is amide formation from 5-diethyl 4-(perfluorophenyl) 2,6-dimethyl-1,4-dihydropyridine-3,4,5-tricarboxylate and l-methionine. Sodium salt formation was performed to improve physicochemical properties, such as solubility of the l-methionine-derived 1,4-dihydroisonicotinamide. The obtained target compound was fully characterized by UV, IR, 1H NMR, 13C NMR, MS, and microanalysis. Full article
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Short Note
(2S,3R,6R)-2-[(R)-1-Hydroxyallyl]-4,4-dimethoxy-6-methyltetrahydro-2H-pyran-3-ol
Molbank 2020, 2020(2), M1140; https://doi.org/10.3390/M1140 - 03 Jun 2020
Viewed by 1818
Abstract
(2S,3R,6R)-2-[(R)-1-Hydroxyallyl]-4,4-dimethoxy-6-methyltetrahydro-2H-pyran-3-ol was isolated in 18% after treating the glucose derived (5R,6S,7R)-5,6,7-tris[(triethylsilyl)oxy]nona-1,8-dien-4-one with (1S)-(+)-10-camphorsulfonic acid (CSA). The one-pot formation of the title compound involved triethylsilyl (TES) [...] Read more.
(2S,3R,6R)-2-[(R)-1-Hydroxyallyl]-4,4-dimethoxy-6-methyltetrahydro-2H-pyran-3-ol was isolated in 18% after treating the glucose derived (5R,6S,7R)-5,6,7-tris[(triethylsilyl)oxy]nona-1,8-dien-4-one with (1S)-(+)-10-camphorsulfonic acid (CSA). The one-pot formation of the title compound involved triethylsilyl (TES) removal, alkene isomerization, intramolecular conjugate addition and ketal formation. The compound was characterized by 1H and 13C NMR spectroscopy, ESI mass spectrometry and IR spectroscopy. NMR spectroscopy was used to establish the product structure, including the conformation of its tetrahydropyran ring. Full article
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Communication
Synthesis of (R) and (S)-3-Chloro-5-(2,4-dimethylpiperazin-1-yl)-4H-1,2,6-thiadiazin-4-ones
Molbank 2020, 2020(2), M1139; https://doi.org/10.3390/M1139 - 01 Jun 2020
Cited by 2 | Viewed by 2075
Abstract
The reaction of 3,5-dichloro-4H-1,2,6-thiadiazin-4-one with (R) and (S)-1,3-dimethylpiperazines (1 equiv), in THF, at ca. 20 °C gives (R) and (S)-3-chloro-5-(2,4-dimethylpiperazin-1-yl)-4H-1,2,6-thiadiazin-4-ones in 70% and 68% yields, respectively. The new compounds were fully characterized. Full article
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Methyl 2-(1-methyl-3-oxoisoindolin-1-yl)acetate
Molbank 2020, 2020(2), M1131; https://doi.org/10.3390/M1131 - 08 May 2020
Cited by 1 | Viewed by 1874
Abstract
In this work, we report a facile access to a 3,3-disubstituted isoindolinone by means of Krapcho decarboxylation reaction of the respective substituted dimethyl malonate derivative. Good isolated yields were obtained under mild reaction conditions. Full article
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Short Note
2-(Fluoromethyl)-4,7-dimethoxy-1-methyl-1H-benzimidazole
Molbank 2020, 2020(2), M1129; https://doi.org/10.3390/M1129 - 01 May 2020
Viewed by 2379
Abstract
Selectfluor (1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)) substitutes the TEMPO free radical with fluorine on 4,7-dimethoxy-1-methyl-2-{[(2,2,6,6-tetramethylpiperidin-1-yl)oxy]methyl}-1H-benzimidazole to give the title compound in a 77% yield. A mechanism is proposed for the formation of this novel methylene fluoride. Full article
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Communication
Synthesis of (R) and (S)-3-Chloro-5-(3-methylmorpholino)-4H-1,2,6-thiadiazin-4-ones
Molbank 2020, 2020(2), M1128; https://doi.org/10.3390/M1128 - 27 Apr 2020
Cited by 1 | Viewed by 1846
Abstract
Reaction of 3,5-dichloro-4H-1,2,6-thiadiazin-4-one with (R) and (S)-3-methylmorpholines (2 equiv), in THF, at ca. 20 °C gave (R) and (S)-3-chloro-5-(3-methylmorpholino)-4H-1,2,6-thiadiazin-4-ones in 95 and 97% yields, respectively. The new compounds were fully characterized. Full article
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Short Note
2,6-exo-8,12-exo-10-Butyl-13-oxa-3,5-dithia-10-azatetracyclo[5.5.1.02,6.08,12]tridecane-9,11-dione
Molbank 2020, 2020(2), M1123; https://doi.org/10.3390/M1123 - 02 Apr 2020
Cited by 2 | Viewed by 2234
Abstract
The title compound was obtained in low yield and spectroscopically characterised. Its X-ray structure was compared with the X-ray structures of other crystallographically-characterised 2-unsubstituted 1,3-dithiolanes. Full article
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Communication
6-Imino-1,2,3,4,8,9,10,11-octahydropyrido[1,2-a]pyrido[1′,2′:1,2]imidazo[4,5-f]benzimidazole-13-one: Synthesis and Cytotoxicity Evaluation
Molbank 2020, 2020(1), M1118; https://doi.org/10.3390/M1118 - 05 Mar 2020
Cited by 2 | Viewed by 1978
Abstract
The first report of an iminoquinone of imidazo[4,5-f]benzimidazole is described. The 2D-NOESY spectrum of 1,2,3,4,8,9,10,11-octahydropyrido[1,2-a]pyrido[1’,2’:1,2]imidazo[4,5-f]benzimidazol-6-amine was used to confirm the location of the imine moiety at the C-6 position of the title compound. Cytotoxicity data from the National Cancer Institute are included. Full article
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Diethyl pyrrole-2,5-dicarboxylate
Molbank 2020, 2020(1), M1117; https://doi.org/10.3390/M1117 - 17 Feb 2020
Cited by 1 | Viewed by 1838
Abstract
The title compound was obtained in moderate yield by a new and unexpected base-induced ring contraction from a 1,4-thiazine precursor. Its X-ray structure showing hydrogen bonded dimers was compared with those of other crystallographically characterised 2-acylpyrroles. Full article
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Communication
1-Phenyl-8-[[4-(pyrrolo[1,2-a]quinoxalin-4-yl)phenyl]methyl]-1,3,8-triazaspiro[4.5]decan-4-one: Synthesis, Crystal Structure and Anti-Leukemic Activity
Molbank 2020, 2020(1), M1113; https://doi.org/10.3390/M1113 - 29 Jan 2020
Cited by 4 | Viewed by 2061
Abstract
1-Phenyl-8-[[4-(pyrrolo[1,2-a]quinoxalin-4-yl)phenyl]methyl]-1,3,8-triazaspiro[4.5]decan-4-one has been successfully synthesized via a multi-step pathway starting from 2-nitroaniline. Structure characterization of this original pyrrolo[1,2-a]quinoxaline derivative was achieved by FT-IR, 1H-NMR, 13C-NMR, X-Ray and HRMS spectral analysis. This title compound shows interesting cytotoxic potential [...] Read more.
1-Phenyl-8-[[4-(pyrrolo[1,2-a]quinoxalin-4-yl)phenyl]methyl]-1,3,8-triazaspiro[4.5]decan-4-one has been successfully synthesized via a multi-step pathway starting from 2-nitroaniline. Structure characterization of this original pyrrolo[1,2-a]quinoxaline derivative was achieved by FT-IR, 1H-NMR, 13C-NMR, X-Ray and HRMS spectral analysis. This title compound shows interesting cytotoxic potential against several human leukemia cell lines (K562, HL60, and U937 cells). Full article
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Graphical abstract

2019

Jump to: 2023, 2022, 2021, 2020

Communication
Novel One-Pot Synthesis of Methyl 4-Hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate: Synthetic and Crystallographic Studies
Molbank 2019, 2019(4), M1085; https://doi.org/10.3390/M1085 - 14 Oct 2019
Cited by 2 | Viewed by 1986
Abstract
A new suitable method of synthesis of methyl 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate by condensation of methyl 2-isothiocyanatobenzoate and methyl malonate is described. The structure of the compound both and by-product methyl 2-(methoxycarbonothioylamino)benzoate was confirmed by means of elemental analysis, 1H NMR, 13C NMR, LC/MS [...] Read more.
A new suitable method of synthesis of methyl 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate by condensation of methyl 2-isothiocyanatobenzoate and methyl malonate is described. The structure of the compound both and by-product methyl 2-(methoxycarbonothioylamino)benzoate was confirmed by means of elemental analysis, 1H NMR, 13C NMR, LC/MS and single crystal X-ray diffraction. UV/Vis and IR spectra of compounds are described. The presence of a strong intramolecular hydrogen bond between the hydroxy group and the carbonyl oxygen atom of the ester group in methyl 4-hydroxy-2-thioxo-1,2-dihydroquinoline-3-carboxylate is shown. The crystal structure of product was stabilized through intermolecular hydrogen bonds. Full article
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Short Note
3-{[(2,3-Dichlorophenyl)amino]methyl}-5-(furan-2-ylmethylidene)-1,3-thiazolidine-2,4-dione
Molbank 2019, 2019(4), M1083; https://doi.org/10.3390/M1083 - 03 Oct 2019
Viewed by 1725
Abstract
The compound 3-{[(2,3-Dichlorophenyl)amino]methyl}-5-(furan-2-ylmethylidene)-1,3-thiazolidine-2,4-dione has been designed, synthesized, and screened for its in vitro antibreast cancer activity, using human breast adenocarcinoma cell lines (MCF-7) and in vitro anti-inflammatory activity. By hemolysis assay, it showed that it has a nonhemolytic and nontoxic effect on human [...] Read more.
The compound 3-{[(2,3-Dichlorophenyl)amino]methyl}-5-(furan-2-ylmethylidene)-1,3-thiazolidine-2,4-dione has been designed, synthesized, and screened for its in vitro antibreast cancer activity, using human breast adenocarcinoma cell lines (MCF-7) and in vitro anti-inflammatory activity. By hemolysis assay, it showed that it has a nonhemolytic and nontoxic effect on human blood cell. The title compound 5, subjected to in vitro activities, showed that it is cytotoxic with an IC50 of 42.30 µM and a good anti-inflammatory agent. The docking results against cyclin dependent kinase 2 (CDK2) (PDB ID: 3QQK) gave insights on its inhibitory activity. Full article
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Short Note
4-[(3,5-Dimethyl-1H-pyrazol-1-yl)methyl]-4-methyl-2-phenyl-4,5-dihydrooxazole
Molbank 2019, 2019(3), M1074; https://doi.org/10.3390/M1074 - 19 Jul 2019
Cited by 1 | Viewed by 2061
Abstract
The compound, 4-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]-4-methyl-2-phenyl-4,5-dihydrooxazole 2 was prepared in high yield, through nucleophilic substitution reaction of the O-tosyl oxazoline derivative 1, by heating in dimethyl sulfoxide (DMSO) and in presence of KOH as base. The structure of the synthesized compound was [...] Read more.
The compound, 4-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]-4-methyl-2-phenyl-4,5-dihydrooxazole 2 was prepared in high yield, through nucleophilic substitution reaction of the O-tosyl oxazoline derivative 1, by heating in dimethyl sulfoxide (DMSO) and in presence of KOH as base. The structure of the synthesized compound was established on the basis of NMR spectroscopy (1H, 13C), MS data and elemental analysis. Full article
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