Synthesis of Some New 6-Methylimid azo [2,1-b] thiazole-5-carbohydrazide Derivatives and their Antimicrobial Activities

Abstract

In this study, 14 new compounds having 6-methyl-N2-(alkylidene/cycloalkylidene)imidazo[2,1-b]thiazole-5-carbohydrazide (3a-g), 3-[[(6-methylimidazo[2,1-b]thiazole-5-yl)carbonyl]amino]-4-thiazolidinone (4a-d) and 4-[[(6-methylimidazo[2,1-b]thiazole-5-yl)carbonyl]amino]-1-thia-4-azaspiro[4.4]nonan/[4.5]decan-3-one (4e-g) structures were synthesized. The structures of the compounds were elucidated by UV, IR, 1H-NMR, 13C-NMR, 1H-13C-COSY, mass spectra and elemental analysis. All compounds synthesized were tested for antimicrobial activity against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis ATCC 14153, Candida albicans ATCC 10231 and Mycobacterium tuberculosis H37Rv. Only 4d and 4f demonstrated antimicrobial activity against S. epidermidis ATCC 12228 (MIC: 19.5 microg/ml and 39 microg/ml, respectively).

Synthesis and Structure-Activity Relationship of N-(3-Oxo-1-Thia-4-Azaspiro[4.5]Decan-4-Yl)Carboxamide Inhibitors of Influenza Virus Hemagglutinin Mediated Fusion

“…Further support was obtained from 1 H-NMR spectra of 4a-4f, 6a-6d and 7a-7d which showed the same resonance at 3.99-3.91 ppm as a quarted. 13 C-NMR spectra of 3a, 4a, 5a, 5b, 6b, 6c, 7a, 7b and 7d showed two signals at about 170.9-167.3 ppm due to carbonyl carbon absorptions. In addition, resonances at about 73.1 and 71.6 ppm (spdec.…”

“…These methods employ a two-step synthesis 13 , or a one-pot three-component condensation. 14 The reaction contains three components: An amine, a carbonyl compound and a sulfanyl acid.…”

“…Infrared (IR) spectra were recorded on a Perkin Elmer 1600 FT infrared spectrophotometer in potassium bromide pellets (υ in cm -1 ). 1 H-NMR spectra were recorded on a Varian UNITY INOVA 500 MHz NMR spectrophotometer using tetramethylsilane as internal standard 13. C-NMR spectra were recorded at 125 MHz using the instrument mentioned above.…”

Antimicrobial and cytotoxic activities of thiazolo[4,5-b]pyridine derivatives

“…Güzeldemirci et al, 2010 [17] S. epidermidis (MIC = 19.5 μg/mL) F. Ur et al, 2004 [18] N Gali et al, 2014 [20] S. aureus (MIC = 12.5 μg/mL) A.A. Bekhit et al, 2003 [19] activities, especially anticancer [10,11], antitripanosomal [12,13], anti-inflammatory [14,15]. Interestingly, the significant antimicrobial activity was also observed for fused thiazoles, especially thiopyrano [2,3-d]thiazoles [16], imidazo [2,1-b]thiazoles [17], azo [2,1-b] thiazoles [18], thiazolo [4,5-d]pyrimidines [19] and benzo[h]thiazolo [2,3-b]quinazolinones [20] (Figure 1). As a part of our research in the field of biologically active fused thiazoles, herein we report the antimicrobial and antiproliferative properties of some thiazolo [4,5-b] pyridine derivatives.…”

Fused Heterocycles: Synthesis and Antitubercular Activity of Novel 6‐Substituted‐2‐(4‐methyl‐2‐substituted phenylthiazol‐5‐yl)H‐imidazo[1,2‐a]pyridine

“…Isoniazid derivatives and pyridine‐containing heterocyclic compounds are known for the antimycobacterial activity . 2‐Anilino‐4‐(thiazol‐5‐yl)pyrimidine derivatives show potent inhibitors of cyclin‐dependent kinase‐2 activity , oxadiazinylimidazopyridines, pyrimidines, and thiazoles ; 6‐methylimidazo[2,1‐ b ]thiazole‐5‐carbohydrazide derivatives show antimicrobial activities ; and oxazolines, oxazoles, thiazolines, and thiazoles to imidazo[1,2‐a]pyridines show antitubercular activity . For searching the new scaffold for antimycobacterial agents, it was thought to synthesize novel clubbed 6‐substituted‐2‐(4‐methyl‐2‐substituted phenylthiazol‐5‐yl) H ‐imidazo[1,2‐ a ]pyridine derivatives and screen for their antitubercular activity.…”