Synthesis of New Heterocyclic Compounds Containing 1,3,4-Thiadiazole Moiety and Their Antibacterial and Antifungal Activities

Abstract

A new compounds of 2-mercapto-5-phenyl-4,6-dione-1,3,5-tiazino [6,5-b][1,3,4] thiadiazole (2), 2-[2-p-methoxyphenyl-4-oxo-1,3-thiazolidin-3-yl]-5-mercapto-1,3,4-thiadiazole (4), 1-[2-(2-amino-1,3,4-thiadiazol-5-ylthio)acetyl] -2,4,5-trihydropyridazin-3,6-dione (7) and 1-[2-(2-amino-1,3,4-thiadiazole-5-ylthio) acetyl]-3-methylpyrazol-5-one (8) were synthesized in good yield via condensation of 2-amino-5-mercapto-1,3,4-thiadiazole (1) with different organic reagents. All new compounds were tested against three strains of Gram negative bacteria (Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris) and two strains of fungi (Candida albicans and Aspergillus niger), comparing these activities with that of the starting material. Compounds (2), (4), and (7) were highly active against all bacteria strains. Compound (1) was highly active against Candida albicans than others while none of the tested compounds were active against Aspergillus niger.

Antimicrobial and Antiquorum‐Sensing Studies. Part 3: Synthesis and Biological Evaluation of New Series of [1,3,4]Thiadiazoles and Fused [1,3,4]Thiadiazoles

“…The arylideneamino- [1,3,4]thiadiazoles possess antimicrobial activity [36][37][38][39]. In addition, thiazolidin-3-yl- [1,3,4]thiadiazoles were extensively investigated for their pharmacological uses, some of these compounds showed antimicrobial activity [40][41][42][43][44]. Considering these published data and in continuation to our previous work [15,16] and in searching for new compounds of potent antimicrobial and antiquorumsensing activities, we described herein the synthesis of new series of [1,3,4]thiadiazoles and fused [1,3,4]thiadiazoles.…”