Catalyst-free direct cross-dehydrogenative coupling of imidazoheterocycles with glyoxal hydrates: an efficient approach to 1,2-diketones.

Org Biomol Chem

College of Chemistry, Chemical and Environmental Engineering, Henan University of Technology, Zhengzhou, Henan 450001, P. R. China.

Published: March 2019

An efficient and convenient methodology for catalyst-free cross-dehydrogenative coupling of imidazoheterocycles with glyoxal hydrates in good yields was developed. This methodology exhibits a broad substrate scope and excellent functional group tolerance and offers a straightforward means to produce different heterocycles such as imidazoheterocyclic quinoxaline, imidazoheterocyclic hydantoin and imidazoheterocyclic α-keto ketamine under relatively mild conditions. Biological evaluation showed that the most potent compound 3m possesses significant in vitro antiproliferative activities against human-derived lung cancer cell lines with an IC50 value of 14.8 μM.

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http://dx.doi.org/10.1039/c9ob00095jDOI Listing

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