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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Four New Picrotoxane-Type Sesquiterpenes From Dendrobium nobile Lindl
Pei Wang1, Xin Chen1,2, Hao Wang1
1Hainan Key Laboratory of Research and Development of Natural Product From Li Folk Medicine, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, Haikou, China.
Abstract:
Four picrotoxane-type sesquiterpenes, dendroterpene A-D (1-4), together with four known compounds (5-8), were isolated from the stems of Dendrobium nobile Lindl. Their structures were elucidated by spectroscopic analysis, X-ray diffraction analysis, analysis of the ECD data according to the Klyne's lactone sector rule, and quantum ECD calculation. Compounds 1 and 2 are two new picrotoxane-type sesquiterpenes with a new carbon skeleton containing a formamide group, which may be derived from the previously reported dendrobiumane B skeleton by the C(9)-C(11) carbon bond cleavage. Compounds 3, 5, 6, and 8 exhibited inhibitory activity against α-glycosidase. Compounds 5 and 6 were cytotoxic against SGC-7901, K562, A549, BEL-7402, and Hela cell lines.
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