[A new chromone glycoside from Cassia siamea lam].

To study the chemical constituents of the stem of Cassia siamea. The compounds were isolated by chromatography on silica gel, and identified on the basis of spectral analysis. Five compounds were isolated and identified as: beta-sitosterol (I), sucrose (II), n-octacosanol (III), 2-methyl-5-(2'-hydroxypropyl)-7-hydroxy-chromone-2'-O-beta-D-glucopyranoside (IV) and piceatannol (V). Compound IV is a new compound. Compounds II, III and V were obtained from this plant for the first time.