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A Customizable Approach for the Enzymatic Production and Purification of Diterpenoid Natural Products
Published on: October 4, 2019
Dengratiols A-D, four new bibenzyl derivatives from Dendrobium gratiossimum
Jiawei Sun1, Jimei Liu1, Yuyu Liu1
1State Key Laboratory of Bioactive Substance and Function of Natural Medicines, CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs, and NHC Key Laboratory of Biosynthesis of Natural Products, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, Beijing 100050, China.
Abstract:
Dengratiol A (1), an unprecedented bibenzyl derivative bearing a tropolone unit together with three pairs of bibenzyl enantiomers (±)-dengratiols B-D [(±)-2-(±)-4], were isolated from Dendrobium gratiossimum Rchb.f. The resolution of enantiomers was performed with chiral HPLC. Their structures were characterized by extensive spectroscopic data analysis and calculated electronic circular dichroism (ECD). A hypothetical biosynthetic pathway for 1 is proposed. Biological assay revealed that (-)-2 showed moderate antiviral effect against IAV with IC50 value of 6.3 μM, and (±)-2 displayed cytotoxic activities against five human tumor cell lines with IC50 values ranging from 15.5 to 42.5 μM.
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