A new biflavone glycoside from flowers of Asystasia gangetica

摘要

The yellow parts of the flowers of Asystasia gangetica were extracted with 85% methanol under reflux. The alcoholic extract was concentrated in vacuo and the aqueous extract was fractionated with solvents of increasing polarity. The ethyl acetate fraction yielded a yellow solid, which was characterized as apigenin 7-O-glucosyl(3'→6'')luteolin 7''-O-glucoside using UV, ~1H, ~1H-~1H COSY, ~(13)C NMR, and mass spectral studies.