Three New Benzophenone Glucosides from the Leaves of Planchonella obovata

Chemical investigation of the EtOH extract of the leaves of Planchonella obovata resulted in the isolation of four benzophenone glucosides, 1-4. of which three, 2-4, are new chemical entities together with five known flavonol glycosides. Their structures were elucidated by spectroscopic analysis. Among the isolated compounds, iriflophenone 2-O-(2,6-di-O-galloyl)-beta-D-glucopyranoside (4) showed some activity (91.4 and 15.0% inhibition at 100 and 10 mu g/ml. resp.) against the alpha-glucosidase of Bacillus stearothermophilus.