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Crepidtumines A and B, Two Novel Indolizidine Alkaloids from Dendrobium crepidatum.

ABSTRACT: Two new indolizidine alkaloids crepidatumines A (1) and B (2) together with the stereoisomer of dendrocrepidine B (3) and known analog dendrocrepine (4) were isolated from D. crepidatum. Their structures were determined by HR-ESI-MS, NMR, and Electronic Circular Dichroism (ECD) experiments together with comparison of analogues. Compound (1) possess a (5/6/6/5) tetra-hetero-cyclic ring, whereas compound (2) contains a tricyclic system with an unusual bridged ring, which are the first report in Nature. The biological evaluation revealed that dendrocrepine (4) displayed a potent hypoglycemic effect in vitro.

SUBMITTER: Xu X

PROVIDER: S-EPMC7293321 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Crepidtumines A and B, Two Novel Indolizidine Alkaloids from Dendrobium crepidatum.

Xu Xiaolin X Chen Xingyue X Yang Runmei R Li Zesheng Z Zhou Houguang H Bai Yanbing Y Yu Meng M Li Biao B Ding Gang G

Scientific reports 20200612 1

Two new indolizidine alkaloids crepidatumines A (1) and B (2) together with the stereoisomer of dendrocrepidine B (3) and known analog dendrocrepine (4) were isolated from D. crepidatum. Their structures were determined by HR-ESI-MS, NMR, and Electronic Circular Dichroism (ECD) experiments together with comparison of analogues. Compound (1) possess a (5/6/6/5) tetra-hetero-cyclic ring, whereas compound (2) contains a tricyclic system with an unusual bridged ring, which are the first report in Na ...[more]

PMID: 32533030

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