Synthesis and screening for antibacterial activity of Schiff's and Mannich bases of isatin and its derivatives

Abstract

Schiff s bases of Isatin and its derivatives were synthesized by reacting isatin and its derivatives with trimethoprim. The N-Mannich bases of the above isatin Schiffs bases were synthesized by condensing acidic 'NH' group of isatin with formaldehyde and secondary amines and screened for their antibacterial activity. All the synthesized compounds showed good activity against Vibrio cholerae non-O1, Shigella boydii, Enterococcus faecalis and Edwardsiella tarda with MIC in the range of 10-25 μg/ml. Some compounds were found to be active against Salmonella typhi [MIC 130-160 μg/ml] and against Vibrio cholerae-O1 [MIC: 75-150 μg/ml].