Drug Action of Sulfonamide Schiff Bases: Structure, Antimicrobial Activity and In-Silico Studies
Abstract
Schiff bases of 2-nitrobenzaldehyde (a) / salicylaldehyde (b) and Sulfadiazine (1), Sulfadimidine (2) and Sulfathiazole (3) are spectroscopically Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible (UV-Vis), Mass, Nuclear Magnetic Resonance (NMR) characterized. The structural confirmation is supported in one case (3b) by single crystal X-ray diffraction studies. The Hirshfeld surface analysis is used to analyze the existence of various weak interactions in 3b. The antimicrobial activity of the compounds is examined against Gram-positive (B. subtilis) and Gram-negative (E. coli) bacteria. The compounds show better antimicrobial efficiency against B. subtilis than E. coli and follow the order 1a > 1 > 1b > 2a > 3a > 2b > 3b > 3 > 2. The toxicity of the compounds has been checked by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay and no toxicity is found up to 200 μg mL-1. The In-silico analysis of the drugs has been computed with dihydropteroate synthase (DHPS) protein and the highest binding strength is calculated for the compound labeled as 1a and hence it may serve as best antibiotic in the series.