Title
7α,20-Epoxy-ent-kaurane Diterpenoids from the Aerial Parts of Isodon pharicus
Author
Zheng-Xi Hu, Miao Liu, Wei-Guang Wang, Xiao-Nian Li, Kun Hu, Xing-Ren Li, Xue Du, Yong-Hui Zhang, Pema-Tenzin Puno, Han-Dong Sun
Year
2018
Journal
Journal of Natural Products
Abstract
A phytochemical investigation of an ethyl acetate extract of the aerial parts of Isodon pharicus led to the isolation of 21 new 7α,20-epoxy-ent-kaurane diterpenoids, pharicins C–W (1–21), and 29 known (22–50) analogues. The structural characterization of 1–21 and assignment of their relative configurations were accomplished by spectroscopic data interpretation, while the structures of 1and 16 were confirmed by X-ray crystallography. The absolute stereostructure of 1 was confirmed by electronic circular dichroism data analysis. Twenty-five of the diterpenoids were screened for their cytotoxic activities against a panel of tumor cell lines, including HL-60, SMMC-7721, A-549, MCF-7, and SW-480. Compounds 11, 16, 38, and 48 exhibited inhibitory activities against these tumor cell lines with IC50 values ranging from 1.01 to 9.62 μM, while 2, 15, 29, and 47 exhibited moderate cytotoxic potency.
Instrument
J-810
Keywords
Circular dichroism, Absolute configuration, Natural products, Medicinal