【摘 要】
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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
【机 构】
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Department of Phytochemistry,School of Pharmacy,Department of Biology
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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 3β, 12β, 25-trihydroxy-20(S), 24(S)-epoxydammarane 3-O-β-D-glucopyranosyl (1→2)-β-D-xylo -pyranoside, 3β, 12β, 25-trihydroxy-20(S), 24(R)-epoxydammarane 3-O-β-D-glucopyranosyl (1→2)-β-D-xylopyranoside and 3β, 12β, 23β, 25-tetrahydroxy-20(S), 24(S)-epoxydammarane 3-O-β-D-glucopyranosyl (1→2)-β-D-xylopyranoside, respectively, on the basis of chemical and spectro -scopic methods.
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