Diversity-oriented One-pot Synthesis of Novel Imidazo[4,5:4,5]benzo[e][1,4]thiazepinones and Benzo[d]imidazolyl Thiazolidinones through pTSA Promoted Cyclization and Evaluation of Antimicrobial and Anti-inflammatory Activities

In contrast to target-oriented synthesis that aims to access precise regions of chemistry, diversity-oriented synthesis via multicomponent synthesis populates chemical space broadly with small molecules having diverse structures. This study has achieved the diversity-oriented synthesis of novel imidazo[4,5:4,5]benzo[e][1,4]thiazepinones (4) and benzo[d]imidazolyl thiazolidinones (5) controlled by the nature of substitution effect of the reaction component. The one-pot reaction of benzimidazole 1, aromatic aldehyde 2, and mercaptoacetic acid 3 leads to the formation of imidazo[4,5:4,5]benzo[e][1,4]thiazepinones (4) with electron-donating groups as substitution on aromatic aldehyde while electron-withdrawing substitutions produced benzo[d]imidazolyl thiazolidinones (5). The title compounds (4) and (5) were evaluated for their antimicrobial and anti-inflammatory activities.