MICROWAVE ASSISTED SYNTHESIS AND MICROBIAL EVALUATION OF -2H-PYRROLO [2, 3-C: 5, 4 C'] DIPYRAZOLE-2, 5 (7H)-BIS-CARBOTHIOAMIDE DERIVATIVES

Abstract

In this study the synthesis of novel carbothiomides derivatives containing pyrazole moiety have been carried out by use of microwave assisted green and efficient process. The starting compound N-phenyl substituted succinamides 5a-b were condensed with substituted benzaldehydes furnished in to bis-heterocyclic chalcones which on treatment with thiosemicarbazide hydrochloride leads to formation of pyrralo dipyrazole carbothiomide derivatives. The structures of all synthesized compounds were determined by FT IR, 1H NMR, 13CNMR spectral analysis techniques. The pyrazole carbothiomide derivatives were selected for evaluation of antimicrobial activities. The in vitro antibacterial screening was carried out against Gram positive bacteria Staphylococcus auras, Bacillus subtilis and Gram negative bacteria Pseudomonas aeruginosa, Escherichia coli. The antibacterial activity was measured in term of zone of inhibition in mm unit and compared with standard antibiotic drug Chloramphenicol. Similarly antifungal evaluation was also evaluated in vitro against fungi Aspergillus niger and Candida albicans. The zone of inhibition was measured in mm and compared with standard antifungal drug Amphotericin-B. The all carbothiomide derivatives showed good anti-bacterial activities against gram positive bacteria and good anti-fungal activities. The compounds 9ai and 9aiv showed potent antifungal activity against Candida albicans than standard drug amphotericin-B at 100 μgm/mL concentration.