Synthesis and evaluation of antimicrobial properties of new Mannich bases of 4,5-disubstituted-1,2,4-triazole-3-thiones

This study presents the synthesis and antimicrobial properties of new Mannich bases of 1,2,4-triazole-3-thiones. New compounds were prepared by the reaction of 4,5-disubstituted-1,2,4-triazole-3-thiones with formaldehyde and various amines. The structures of the prepared compounds were established on the basis of spectral methods (H-1 NMR, C-13 NMR). All synthesized compounds were tested for in vitro antimicrobial activity by broth microdilution method using the reference Gram-positive and Gram-negative bacterial strains and fungi belonging to Candida spp. Antimicrobial assays revealed that newly synthesized compounds: 8, 9, 10, 15, and 17 showed some antimicrobial activity against reference Gram-positive bacteria or yeasts with good to moderate activity of 9 and 15 towards B. subtilisATCC 6633. [GRAPHICS] .