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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.
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 24 (S) -epoxydammarane 3-ObD-glucopyranosyl (12) -bD-xylo-pyranoside, 3b, 12b, 25- trihydroxy- 20 (S), 24 -xylopyranoside and 3b, 12b, 23b, 25-tetrahydroxy-20 (S), 24 (S) -epoxydammarane 3-ObD-glucopyranosyl, respectively, on the basis of chemical and spectro -scopic methods.