[Studies on the chemical constituents of the root tube from Pteroxygonum giraldii].

To study the chemical constituents of the root tube from Pteroxygonum giraldii. Column chromatography and spectral analysis were used to isolate and identify the constituents. Ten compounds were isolated and identified as beta-sitosterol (I), beta-sitosterol glucoside (II), 4', 5,5', 7-tetrahydroxy-3'-methoxy-3'-O-alpha-L-arabinopyranosyl flavone (III), gallic acid (IV), myricetin (V), annulatin (VI), 5,5', 7-trihydroxy-2',3-dimethoxy-4'-O-beta-D-glucopyranosyl flavone (VII), 2', 5,5',7-tetrahydroxy -3-methoxy-4'-O-beta-D-glucopyranoside flavone (VIII), myricetin-3-O-alpha-L-rhamnopyranoside (IX) and myricetin-3,4'-dimethyl ether( X). Compounds I, II, V, VIII and X are isolated from Pteroxygonum giraldii for the first time.