METHYLATED A-TYPE PROANTHOCYANIDINS AND RELATED METABOLITES FROM CASSIPOUREA-GUMMIFLUA

The range of natural dimeric A-type proanthocyanidins is extended by i dentification of two new dimeric afzelechins in the form of 7-OMe-epia fzelechin-(4 beta-->8,2 beta-->O-->7)-epiafzelechin and 7-OMe-epiafzel echin-(4 beta-->8, 2 beta-->O-->7)-ent-afzelechin. These are accompani ed in the stem bark of Cassipourea gummiflua by the related metabolite s afzelechin, kaempferol-3-O-alpha-L-rhamnopyranoside, afzelechin-3-O- alpha-L-rhamnopyranoside, epiafzelechin (4 beta-->8, 2 beta-->O-->7)-e piafzelechin and epiafzelechin-(4 beta-->8,2 beta-O-->7)-ent-afzelechi n, the latter three compounds being reported from a natural source for the second time.