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Updated: Jan 24, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Design, synthesis and biological evaluation of new ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F) derivatives as
Chenliang Zhao1, Yinxiao Du2, Yixuan Xia3
1Guizhou Key Laboratory of Miao Medicine, Guizhou University of Traditional Chinese Medicine, 50 Cityeast Road, Guiyang, Guizhou 550002, PR China; School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, China.
Abstract:
Ent-11α-hydroxy-15-oxo-kaur-16-en-19-oic-acid (5F) is a naturally occurring ent-kaurane diterpenoid isolated from the traditional Chinese herbal medicine Pteris semipinnata L., a fern plant known for its reported antitumor properties. In an effort to expand the pool of natural scaffold-based compounds for anticancer purposes, novel derivatives of 5F have been synthesized by modifying functional groups at C-11 and C-19. These derivatives have been evaluated for their anti-proliferative activities against a panel of cancer cell lines. Among them, compound 13 exhibited approximately 27 times greater potency than 5F in HCT116 cells, with an IC50 value of 0.232 μM. In an HCT116 xenograft mouse model, 13 displayed superior tumor inhibitory effects compared to fluorouracil (5-FU).
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