Design and synthesis of novel enantiomerically enriched morpholino [4, 3–a] benzimidazole derivatives as potential bioactive agents

Abstract

A series of chiral morpholino [4, 3-a] benzimidazole derivatives were synthesized effectively from (S)-(-)-2-(α-hydroxyethyl)-benzimidazole and phenacyl bromide derivatives using an efficient synthetic protocol in good yields and moderate diastereoselectivities. The substrate controlled diastereoselective route makes available structurally attractive morpholine-fused benzimidazole derivatives with two chiral centers in enantiomerically enriched forms. The preliminary biological evaluation shows scope for potential applications.

Graphical Abstract

Keywords:

• L-(+)-lactic acid
• chiral benzimidazole
• morpholine
• diastereoselective reductions
• intramolecular cyclization

Acknowledgments

PKT is thankful to UGC-BSR, New Delhi for the JRF and SRF awards. Authors express sincere thanks to Dr. Dhanji P. Rajani, Microcare Laboratory, Surat, for availing the antimicrobial screening facilities for the compounds herein.

Supplementary data

Supplemental data (full experimental detail, ¹H and ¹³C NMR spectra, Mass spectra, and HPLC analyses) can be accessed on the publisher’s website.