Chemical Evaluation of Betula Species in Japan. IV. Constituents of Betula davurica

抄録

The constituents of Betula davurica PALL. were identified as follows : Fresh leaves : 12-O-acetylbetulafolieneteraol oxide, I, 5, 8-dihydroxy-6, 7-dimethoxyflavone, rutin. Outer bark : betulin, betulin 3-O-caffeate, oleanolic acid, oleanolic acid 3-O-acetate, 3β-acetoxy-12α-hydroxyoleanan-28, 13β-olide, betulinic acid 3-O-caffeate, oleanolic acid 3-O-caffeate, butulonic acid. Inner bark : acerogenin E, (3R)-3, 5'-dihydroxy-4'-methoxy-3', 4"-oxo-1, 7-diphenyl-1-hep-tene, 17-O-methyl-7-oxoacerogenin E^*, 15-methoxy-17-O-methyl-7-oxoacerogenin E^*, (-)-lyoniresinol 3α-O-β-D-xylopyranoside (=nudiposide), (+)-catechin, (+)-catechin 7-O-β-D-xylopyranoside, 3, 4, 5-trimethoxyphenol β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside, monogynol A, roseoside. Root bark : betulin 3-O-caffeate, 3β, 27-dihydroxyolean-12-en-28-oic acid 27-O-caffeate. The two compounds with an asterisk are new.