An efficient synthesis of quinoxaline derivatives from 4-chloro-4-deoxy-α-d-galactose and their cytotoxic activities

A novel and efficient method for the synthesis of quinoxaline derivatives has been developed. Isopropylidenation of 4-chloro-4-deoxy-α-d-galactose with 2,2-dimethoxypropane, followed by selective hydrolysis, afforded 2,3-O-isopropylidene-4-chloro-4-deoxy-d-galactose di-methyl acetal (3) as a sole product. Oxidation of compound 3 with (Bu3Sn)2O–Br2 gave corresponding hex-5-ulose derivative in high yields. The hex-5-ulose derivative reacted with o-phenylenediamines under neutral conditions to afford quinoxaline derivatives in reasonable yields. The in vitro cytotoxic activities of these quinoxaline derivatives were investigated.

Graphical abstractNovel synthesis and preliminary SAR study of some new quinoxaline derivatives were carried out.Figure optionsDownload full-size imageDownload as PowerPoint slide