To investigate how structural modifications affect tuberculostatic potency, we synthesized seven new piperidinothiosemicrabazone derivatives -, in which three of them had a pyrazine ring replacing the pyridine ring. Derivatives - and - exhibited significant activity against the standard strain (minimum inhibitory concentration (MIC) 2-4 μg/mL) and even greater activity against the resistant strain (MIC 0.5-4 μg/mL).
View Article and Find Full Text PDFThree new 2,6-disubstituted thiosemicarbazone derivatives of pyridine, namely, 2-{amino[6-(pyrrolidin-1-yl)pyridin-2-yl]methylidene}-N,N-dimethylhydrazine-1-carbothioamide, CHNS, 2-{amino[6-(piperidin-1-yl)pyridin-2-yl]methylidene}-N,N-dimethylhydrazine-1-carbothioamide, CHNS, and 2-[amino(6-phenoxypyridin-2-yl)methylidene]-N,N-dimethylhydrazine-1-carbothioamide monohydrate, CHNOS·HO, have been synthesized and characterized by NMR spectroscopy and low-temperature single-crystal X-ray diffraction. In addition, their antibacterial and anti-yeast activities have been determined. The ability of the tested compounds to inhibit bacterial growth was comparable to vancomycin as a reference drug.
View Article and Find Full Text PDFIn this study, six new 2,6-disubstituted thiosemicarbazone derivatives of pyridine were synthesized (4−9), and their tuberculostatic activity was evaluated. All of them showed two- to eightfold higher activity (minimum inhibitory concentration (MIC) 0.5−4 µg/mL) against the resistant strain compared with the reference drug.
View Article and Find Full Text PDFIn this study, three new organic ligands N'-(benzylidene)-6-chloropyrazine-2-carbohydrazonamide (L), 6-chloro-N'-(4-nitrobenzylidene)picolinohydrazonamide(L), and N'-(benzylidene)-4-chloropicolinohydrazonamide (L) and three copper coordination compounds (Cu(L)Cl, Cu(L)Cl and Cu(L)Cl) based on them were synthesized. All obtained compounds were characterized using appropriate analytical techniques: elemental analysis (EA), thermogravimetric analysis (TG-DTG), Fourier transform infrared spectroscopy (FTIR) and flame-atomic absorption spectrometry (F-AAS). These methods of physicochemical analyses helped to assume that the complexation in three cases proceeds in a bidentate manner.
View Article and Find Full Text PDFThree new 4-phenylpicolin derivatives with a thiosemicarbazone structure were synthesized and evaluated for tuberculostatic activity. The compounds were obtained by the condensation of methyl 4-phenylpicolonimidate with the corresponding cycloalkylamino-1-carbothiohydrazides. The H NMR temperature spectra obtained showed proton lability at the nitrogen atom N2, and X-ray crystallography confirmed the zwitterionic structure of all products.
View Article and Find Full Text PDFFour novel methyl 4-phenylpicolinoimidate derivatives of hydrazone have been synthesized and evaluated for their antimicrobial activity, including tuberculostatic activity. The compounds obtained are condensates of hydrazonamide or hydrazide with 5-nitro-2-furaldehyde or 5-nitro-2-thiophenecarboxaldehyde. The antimicrobial activity of the tested compounds varied.
View Article and Find Full Text PDFFour new picolinohydrazonamide derivatives, namely, 6-methyl-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide, CHNOS, 6-chloro-N'-(morpholine-4-carbonothioyl)picolinohydrazonamide methanol monosolvate, CHClNOS·CHOH, 6-chloro-N'-(4-phenylpiperazine-1-carbonothioyl)picolinohydrazonamide, CHClNS, and 6-chloropicolinohydrazonamide, CHClN, have been synthesized and characterized by NMR spectroscopy and single-crystal low-temperature X-ray diffraction. In addition, their antibacterial and anti-yeast activities have been determined. The first three compounds adopt the zwitterionic form in the crystal structure regardless of the presence or absence of solvent molecules in the structure.
View Article and Find Full Text PDFThe series of new 4-substituted picolinohydrazonamides were synthesized (6-25) and evaluated for tuberculostatic activity. Compounds having a hydrophilic cyclic amine such as morpholine and pyrrolidine at the end of the thiosemicarbazide chain, exhibited the highest antimycobacterial activity. The antimycobacterial activity of compounds 6, 11, and 15 (MIC 0.
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