Lemon juice mediated reaction under ultrasound irradiation: synthesis of indolofuroquinoxalines as potential anticancer agents.

A non-hazardous synthetic methodology has been developed for the preparation of compounds based on indolofuroquinoxaline framework. The lemon juice that is known to play the role of a biocatalyst in various organic reactions was used for this purpose. A number of indolofuroquinoxaline derivatives were prepared via the lemon juice mediated condensation of methyl 2-(2-chloro-1H-indol-3-yl)-2-oxoacetate or its N-alkyl derivatives with 1,2-diamines under ultrasound irradiation. All the synthesized compounds were screened via an MTT assay for their potential anticancer properties in vitro using a number of cancerous cell lines including MDA-MB 231, and MCF7, K562, Colo-205 and IMR-32 and the non-cancerous HEK293 cell line. Compounds 3a, 3b and 3c showed promising growth inhibition against K562, MDA-MB 231 and MCF7 cell lines but no significant effects on HEK293 cell line suggesting their selectivity towards cancer cells. Moreover, according to their IC50 values all these compounds appeared to be relatively more potent towards K562 cell line over MDA-MB 231 and MCF7 cell lines indicating their potential against leukemia.