Flavonoids from the fruits of (L.) Skeels with anti--glucosidase activity.

Eleven flavonoids including one new flavonol glycoside, quercetin-3--(2--L-rhamnopyranosyl)--D-glucuronopyranosyl methyl ester (1), were isolated for the first time from the fruits of (L.) Skeels (Phyllanthaceae). Their structures were determined by extensive spectroscopic data. The known flavonoids, quercetin-3---D-glucuronide methyl ester (3), quercetin-3--(2''--L-rhamnopyranosyl-6''---L-rhamno pyranosyl)--D-glucopyranoside (), myricetin (), and 6-methoxy-naringenin () were isolated for the first time from the genus . Flavonoids , and (IC = 6.01, 6.32, and 7.84 μM, respectively) showed stronger -glucosidase inhibitory activities than the positive control, acarbose (IC = 306.45 μM). The fruits of might be further developed as an anti-diabetic food supplement.