FLAVAN-3-OLS AND PROANTHOCYANIDINS FROM CISTUS-INCANUS

Four monomeric and seven oligomeric flavanoids have been identified from a Cistus incanus subspecies traditionally used for treatment of skin diseases in northern parts of Greece and identified as subsp. tauricus. Flavan-3-ols are (+)-catechin, (+)-gallocatechin, the novel (+)-gallocatechin 3-gallate and the rarely occurring (+)-catechin 3-O-alpha-L-rhamnoside; proanthocyanidins are procyanidins B1 and B3, gallocatechin-(4-alpha-->8)-gallocatechin, its novel (4-alpha-->6)-regioisomer, gallocatechin-(4-alpha-->8)-catechin, the tentatively identified novel catechin-(4-alpha-->8)-gallocatechin and the trimer gallocatechin-(4-alpha-->8)-gallocatechin-(4-alpha-->8)-catechin. The uncommon flavanone 2R,3R-dihydromyricetin was also obtained.