Synthesis and biological activities of natural flavonoid diosmetin and its derivatives

Abstract

Four natural flavonoids 3′-0-methyldiosmetin (1), diosmetin-7-0-β-D-glucoside (2), diosmetin-7-0-β-Z)-galacto-side (3), 3′-0-methyldiosmetin-7-0-β-Z)-glucoside (4), and eight new diosmetin derivatives 3′-0-methyldiosmetin-7-O-P-D-galactoside (5), diosmetin-7-0-β-D-acetylglucoside (6), diosmetin-7-0-β-D- acetylgalactoside (7), 3′-0-methyl- dios-metin-7-0-β-D- acetylglucoside (8), 3′-0-methyldiosmetin-7-0-β-D-galactoside (9), 7-O-isopentyldiosmetin (10), 7-O-prenyl-diosmetin (11) and 7-0-farnesyl- 3′-0-methyldiosmetin (12) were synthesized from hesperidin by reaction steps including de-hydrogenation, selective methylation, glycoside hydrolysis, glycosylation under phase transfer catalytic condition, O-prenylation and O-farnesylation, respectively. Their structures were confirmed by NMR, IR and MS techniques. The synthesized compounds were evaluated for biological activity against four human cancer cell lines by the standard MTT [3-(4,5- dimethylthiazol-2-yl)-2,5-diphenytetrazolium bromide] method, and the results showed that 6, 10 and 11 exhibited moderate cytotoxicity against SMMC-7721, MCF-7 and SW480 cancer cell lines. © 2012 Chinese Chemical Society & SIOC, CAS.