SYNTHESIS, CHARACTERIZATION AND STUDY OF BIOLOGICAL ACTIVITIES OF MANNICH BASES DERIVED FROM 4-(FURAN-2-YL-METHYLENEAMINO)-3-(2- HYDROXYPHENYL)-1H-1,2,4-TRIAZOLE-5-THIONE

Abstract

Triazole nucleus has been studied a lot since the last decade because of its various potent biological activities. The pharmacological application of triazoles has been widely recognized and well documented. Allocating various biological activities of triazole derivative in one place has been the milestone for new research towards this moiety. Triazole derivatives such as Schiff bases have been introduced as the potent bioactive compound. They possess various biological activities and are mostly derived from the triazole nucleus via condensation of primary amino compounds with aldehyde or ketone. However, there is not much documentation about the Mannich bases as their study has begun lately. Mannich bases are the β−aminoketone which are generally formed when amine, aldehyde and carbon acid reacts. Mannich bases have shown multiple biological activities such as antibacterial, antifungal, antiviral, anticancer, etc. Schiff base (4) was converted into thione based Mannich bases (5a and 5b) by reaction with diphenylamine/piperazine in presence of formaldehyde in ethanol. These newly synthesized thione based Mannich bases were characterized by elemental analysis such as UV, FT-IR, 1 H-NMR and 13C-NMR. These Mannich bases were also tested against several bacterial and fungal strains. Mannich bases containing Piperazine moiety (5b) showed better antifungal property than Mannich bases with diphenylamine moiety (5a) whereas 5a showed better antibacterial activity than 5b.