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Updated: Mar 14, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Isolation, Structure Elucidation, and Absolute Configuration of Highly Oxygenated Germacranolides from Carpesium
Qing-Xin Liu1,2, Yong-Xun Yang2, Jian-Ping Zhang2
1School of Traditional Chinese Medicine, China Pharmaceutical University , Nanjing 210009, People's Republic of China.
Abstract:
The new highly oxygenated germacranolides cernuumolides A-J (1-10) and the known compounds 11-20 were isolated from Carpesium cernuum. Among these compounds, 1-4 are 11-methoxymethylgermacranolides and 5-7 as well as 11-17 are 2,9-hemiacetal-linked germacranolides. Their structures were elucidated using NMR and HRESIMS analyses, and X-ray diffraction studies were used to confirm the absolute configurations of 1, 2, 5, 6, 8, and 9. Cernuumolides A-J were evaluated for their in vitro cytotoxicity against the A549, HCT116, MDA-MB-231, and BEL7404 cell lines, and 8 exhibited moderate cytotoxicity with IC50 values in the 0.87-2.02 μM range.
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