Two new flavanols from Glycosmis pentaphylla

Two new flavanols, glycoflavanones A (1) and B (2), which were found to possess α-pyrone moiety, together with five known compounds 4′-O-methylgallocatechine (3), β-sitosterol (4), alphitol (5), 3,4-dimethoxy-5-hydroxy-trans-cinnamyl alcohol (6), and oxyresveratrol (7), were isolated from the stems of Glycosmis pentaphylla by normal-phase and reverse-phase silica gel column chromatography. Their structures were determined on the basis of chemical and spectroscopic analyses.