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Updated: Jun 1, 2026

Applications of Liquid-Chromatography Tandem Mass Spectrometry in Natural Products Research: Tropane Alkaloids as a Case Study
Published on: March 8, 2024
Alisol C 23-acetate from the rhizome of Alisma orientale
Zha-Jun Zhan1, Hong-Ling Bian, Wei-Guang Shan
1College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China.
Abstract:
THE TITLE COMPOUND [SYSTEMATIC NAME: 11β-hydr-oxy-24,25-ep-oxy-3,16-oxo-protost-13 (17)-en-23-yl acetate], C(32)H(48)O(6), a protostane-type triterpenoid, was isolated from the Chinese herbal medicine alismatis rhizoma (the rhizome of Alisma orientalis Juzep). The mol-ecule contains four trans-fused rings, viz. three six-membered and one five-membered ring. Two of the six-membered rings have slightly distorted half-chair conformations, while the third exhibits a chair conformation. The five-membered ring is almost planar. An inter-molecular O-H⋯O hydrogen bond between the hydr-oxy and ep-oxy groups and intra- and intermolecular C-H⋯O hydrogen bonds are observed.
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