Synthesis, antibacterial, antifungal and anti-HIV activities of Schiff and Mannich bases derived from isatin derivatives and N-[4-(4'-chlorophenyl)thiazol-2-yl] thiosemicarbazide.

Isatin, its 5-chloro and 5-bromo derivatives have been reacted with N-[4-(4'-chlorophenyl)thiazol-2-yl] thiosemicarbazide to form Schiff bases and the N-Mannich bases of these compounds were synthesized by reacting them with formaldehyde and three secondary amines. Their chemical structures have been confirmed by means of IR, 1H-NMR data and by elemental analysis. Investigation of antimicrobial activity of compounds was done by agar dilution method against 28 pathogenic bacteria, 8 pathogenic fungi and anti-HIV activity against replication of HIV-1 (IIIB) in MT-4 cells. Among the compounds tested 1-[N,N-dimethylaminomethyl]-5-bromo isatin-3-{1'-[4"-(p-chlorophenyl) thiazol-2"-yl] thio semicarbazone} 10 showed the most favourable antimicrobial activity.