Synthesis and spectral characteristics of Ni(II) 1-aryl-3-aryl(alkyl)-5-(benzothiazole-2-yl)formazanates

Novel mono-and binuclear metal complexes of Ni(II) based on 1-aryl-3-aryl(alkyl)-5-(benzothiazole-2-yl)formazanes were synthesized and their structures were studied by the electronic and IR spectroscopy, mass spectrometry and megnetochemical methods.     

A spectral-kinetic study of the photochemical properties of 1-aryl-3-alkyl-5-(benzothiazol-2-yl)formazans

Photochemical transformations of 1-aryl-3-alkyl-5-(benzothiazol-2-yl)formazans under continuous irradiation conditions were studied by means of electronic absorption spectroscopy. It was shown that thermally reversible photoisomerization about the C=N bond occurred during irradiation.     

Synthesis of 1-(benzothiazol-2-yl)-5-(o-hydroxyphenyl)-1H-1,2,4-triazoles

Recyclization of 4-oxo-1,3-benzoxazinium perchlorates by the action of benzothiazolylhydrazine gave previously unknown benzothiazolyl-substituted 1,2,4-triazoles that attract interest as potential biologically active substances. The structure of the isolated compounds was determined on the basis of their IR and ¹H and ¹³C NMR spectra.     

Synthesis and molecular structure of 1-(pyrimidin-2-yl)-2-(4-aryl-1,3-thiazol-2-yl)hydrazines

Reactions of some 2-hydrazinopyrimidine hydrochlorides with potassium thiocyanate gave 1-(pyrimidin-2-yl)thiosemicarbazides which underwent Hantzsch condensation with aryl chloromethyl ketones to produce 1-(pyrimidin-2-yl)-2-(4-aryl-1,3-thiazol-2-yl)hydrazine hydrochlorides. The protonation was accompanied by mutually dependent tautomeric rearrangements of heterocyclic fragments.     

Synthesis and tautomerism of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1-benzimidazoles

An efficient method has been developed for the synthesis of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1H-benzimidazoles by cyclocondensation of 2-acylmethyl-1H-benzimidazoles benzoylhydrazones with DMF dimethylacetal. The tautomerism of the compounds obtained via migrations of a proton between the pyrazole nitrogen atoms has been studied by ¹H NMR. The more stable tautomers have electron acceptor aryl substituents placed at position 3 of the pyrazole ring and electron donor aryl substituents or a methyl at position 5. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1370–1377, September, 2006.     

Synthesis and properties of 1,3-diphenyl-5-(benzothiazol-2-yl)-6-R-verdazyls

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Synthesis and reactivity of 2-(benzothiazol-2-yl)-1-bromo-1,2-ethanedione-1-arylhydrazones

The novel, highly versatile 2-(benzothiazol-2-yl)-1-bromo-1,2-ethanedione-1-arylhydrazones 3 were prepared and their behavior toward some nucleophiles was investigated. Thus, reaction of 3 with the sodium salt of malononitrile afforded the aminopyrazolecarbonitriles 5 that undergo cyclocondensation with hydrazine, formic acid, and formamide to give the corresponding pyrazolo[3,4-d]pyridazine 6, pyrazolo[3,4-d]pyrimidinone 7, and pyrazolo[3,4-d]pyrimidine 8 derivatives, respectively. Similarly, reactions of 3 with each of acetylacetone, dibenzoylmethane, and benzoylacetonitrile afforded the corresponding pyrazole derivatives 9, 10, and 11, respectively. The latter products undergo cyclocondensation with hydrazine to afford the corresponding pyrazolo[3,4-d]pyridazines 12, 13, and 14, respectively. © 1997 John Wiley & Sons, Inc.     

Synthesis and spectral properties of 3-(2-aryl-5-methyl-1,3-oxazol- 4-yl)-2-(2,5-dimethylthiophen-3-yl)cyclopent-2-en-1-ones

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Synthesis of 5-Amino-1-aryl-4-(4-aryl-1,3-thiazol-2-yl)- 2,3-dihydro-1H-pyrrol-3-ones*

Reactions of 2-(4-aryl-1,3-thiazol-2-yl)-3-oxo-4-chlorobutyronitriles with primary aromatic amines result in nucleophilic substitution of the chlorine atom by amino group, followed by intramolecular addition of the secondary amino group to the cyano group. The products are 5-amino-1-aryl-4-(4-aryl-1,3-thiazol-2-yl)- 2,3-dihydro-1H-pyrrol-3-ones which are structurally related to the known antiischemic drugs.     

Synthesis of 3-alkylmercapto-2-aryl(alkyl) pyrimidazoles

Summary Conditions were found for replacing the halogen in 3-bromo-2-alkyl(aryl)pyrimidazoles by the alkylmercapto group.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1671–1673, September, 1965     

Synthesis,Structure, and Anti-influenza Activity of 2-(Adamantan-1-yl)-5-aryl-1,3,4-oxadiazoles and 2-(Adamantan-1-yl)-5-aryltetrazoles

Two series of new adamantyl derivatives of polynitrogen heterocycles, 2-(adamantan-1-yl)-5-aryl- 1,3,4-oxadiazoles and 2-(adamantan-1-yl)-5-aryl-2H-tetrazoles, have been synthesized, and their structure has been determined by NMR spectroscopy, mass spectrometry, and X-ray analysis. Biological studies in vitro have revealed high inhibitory activity of some of the synthesized 2-(adamantan-1-yl)-5-aryl-2H-tetrazoles against H1N1 influenza A viruses in combination with a relatively low selectivity.     

Synthesis and antimycobacterial screening of new N-(4-(5-aryl-3-(5-methyl-1,3,4-oxadiazol-2-yl)-1H-pyrazol-1-yl)phenyl)-4-amide derivatives

This article demonstrates the synthesis, characterization and the study of in vitro antitubercular activities of twenty four new N-(4-(5-aryl-3-(5-methyl-1,3,4-oxadiazol-2-yl)-1H-pyrazol-1-yl)phenyl)-4-amide derivatives(8a–x). The antitubercular activity of the compounds against Mycobacterium tuberculosis H37Rv(MTB) revealed that 2-chloro-N-(4-(5-(4-chlorophenyl)-3-(5-methyl-1,3,4-oxadiazol-2-yl)-1H-pyrazol-1-yl)phenyl)benzamide(8n) is the most promising lead molecule with a MIC of1.56 mg/m L, while the corresponding unsubstituted benzamide derivative(8o) is the next most active molecule with a MIC of 3.13 mg/m L. Interestingly, the pyrazole intermediate 5b containing chlorophenyl and N-acylcarbohydrazide substituents also showed significant activity(MIC = 3.13 mg/m L). Further, the active molecules did not show toxicity against a normal NIH 3T3 cell line, signifying their suitability for further drug development.     

Synthesis of 3-(3-Acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones

A method is proposed for the synthesis of 3-(3-acetyl-5-aryl-2,3-dihydro-1,3,4-oxadiazol-2-yl)chromones which consists of the conversion of 3-formylchromones to aroylhydrazones and their subsequent heterocyclization using acetic anhydride.     

Haloacetylated enol ethers. 13. Synthesis of N-[1-aryl(alkyl)-3-oxo-4,4,4-trichloro-1-buten-1-yl]-o-phenylenediamines and 2-trichloromethyl-4-aryl-3H-1,5-benzodiazepines

The synthesis and isolation of the intermediates N-[1-aryl(alkyl)-3-oxo-4,4,4-trichloro-1-buten-1-yl]-o-phenylenediamines 2a-f and the corresponding 2-trichloromethyl-4-aryl-3H-1,5-benzodiazepines 3c-g or benzimidazoles 4a-b derivatives obtained from the intramolecular cyclization of 2a-f or from direct cyclo-condensation reaction of β-alkoxyvinyl trichloromethyl ketones 1a-g with o-phenylenediamine, is reported. Depending of the structure of the β-alkoxyvinyl trichloromethyl ketones or the N-[1-aryl(alkyl)-3-oxo-4,4,4-trichloro-buten-1-yl]-o-phenylenediamines and the reactions conditions, benzimidazoles or 3H-1,5-benzodiazepines were obtained.     

Synthesis and structure of N-(4,6-dimethylpyrimidin-2-yl)-2-(5-phenyl-2H-tetrazol-2-yl)acetohydrazide and 1-(4,6-dimethylpyrimidin-2-yl)-3-[(5-phenyl-2H-tetrazol-2-yl)methyl]-1H-pyrazol-5-ol

Russian Journal of Organic Chemistry - New tetrazolyl derivatives of pyrimidine were synthesized containing various linker groups. The structure of these compounds was established by NMR...     

Synthesis and mass spectral studies of 1-[5-chloro-1-substituted-2(1H)-pyrazin-2-on-3-yl]-5-aryl-3-methylpyrazoles

Sixteen new 1-[5-chloro-1-substituted-2(1H)-pyrazin-2-on-3-yl]-5-aryl-3-methylpyrazoles V have been synthesized by condensation of 5-chloro-1-substituted-3-hydrazino-2(1H)-pyrazin-2-ones III and 1-aryl-1,3-butanediones IV in dry 1,4-dioxane. The general mass spectral fragmentation mode of these compounds has been studied.     

Synthesis of 1-aryl-3-（3,4-dihydro-2H-chromen-5-yl） ureas as TNF-α inhibitors

A new series of compounds,1-aryl-3-(3,4-dihydro-2H-chromen-5-yl) ureas,have been synthesized and their structures were confirmed by FAB-MS and ~1H NMR.The preliminary pharmacological screening showed that these compounds inhibited TNF-αproduction in lipopolysaccharide (LPS)-stimulated THP-1 cells.     

Synthesis,spectral and electrochemical properties of halogenated 6-alkyl-5-aryl-1-(benzo[d]thiazol-2-yl)-3-phenylverdazyls and 5-aryl-1-(benzo[d]thiazol-2-yl)-3-phenyl-6-vinylverdazyls

Chemistry of Heterocyclic Compounds - A sequence of alkylation, cyclization, and oxidation reactions was used to convert 5-aryl-1-(benzo[d]thiazol-2-yl)-3-phenylformazans into...