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Chromatographic Purification of Highly Active Yeast Ribosomes
Published on: October 24, 2011
Three New Highly Oxygenated Germacranolides from Carpesium Divaricatum and Their Cytotoxic Activity
Tao Zhang1, Jin-Guang Si2, Qiu-Bo Zhang3
1Institute of Medicinal Plant Development, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100193, China. zt830423@163.com.
Abstract:
Three new highly oxygenated (2⁻4), and two known (1 and 5) germacranolides, were isolated from the whole plant of Carpesium divaricatum. The planar structures and relative configurations of the new compounds were determined by detailed spectroscopic analysis. The absolute configuration of 1 was established using the circular dichroism (CD) method and X-ray diffraction, and the stereochemistry of the new compounds 2⁻4 were determined using similar CD spectra with 1. The new compound 2 and the known compound 5 exhibited potent cytotoxicity against hepatocellular cancer (Hep G2) and human cervical cancer (HeLa) cells, superior to those of the positive control cis-platin.
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