Three new dammarane-type glycosides (1-3) had been isolated from the aerial part of Gynostemma pentaphyllum (Thunb) Makino. The structures of compounds 1-3 had been elucidated as 3b, 12b, 25-trihydroxy-20(S), 24(S)-ep...Three new dammarane-type glycosides (1-3) had been isolated from the aerial part of Gynostemma pentaphyllum (Thunb) Makino. The structures of compounds 1-3 had been elucidated as 3b, 12b, 25-trihydroxy-20(S), 24(S)-epoxydammarane 3-O-b-D-glucopyranosyl (12)-b-D- xylo -pyranoside, 3b, 12b, 25-trihydroxy-20(S), 24(R)-epoxydammarane 3-O-b-D-glucopyranosyl (12) -b-D-xylopyranoside and 3b, 12b, 23b, 25-tetrahydroxy-20(S), 24(S)-epoxydammarane 3-O-b-D- glucopyranosyl (12)-b-D-xylopyranoside, respectively, on the basis of chemical and spectro -scopic methods.展开更多
文摘Three new dammarane-type glycosides (1-3) had been isolated from the aerial part of Gynostemma pentaphyllum (Thunb) Makino. The structures of compounds 1-3 had been elucidated as 3b, 12b, 25-trihydroxy-20(S), 24(S)-epoxydammarane 3-O-b-D-glucopyranosyl (12)-b-D- xylo -pyranoside, 3b, 12b, 25-trihydroxy-20(S), 24(R)-epoxydammarane 3-O-b-D-glucopyranosyl (12) -b-D-xylopyranoside and 3b, 12b, 23b, 25-tetrahydroxy-20(S), 24(S)-epoxydammarane 3-O-b-D- glucopyranosyl (12)-b-D-xylopyranoside, respectively, on the basis of chemical and spectro -scopic methods.