Bufadienolides from the Eggs of the Toad Bufo bufo gargarizans and Their Antimelanoma Activities

作者：Shiwen Zhou, Jing-yu Quan, Zi-wei Li, Ge Ye, Zhuo Shang, Ze-ping Chen, Lei Wang, Xin-yuan Li, Xiao‐Qi Zhang, Jie Li, Jun-Shan Liu, Hai‐Yan Tian · 发表于：Journal of Natural Products · 年份：2021 · DOI：10.1021/acs.jnatprod.0c00840 · 被引用次数：25 · 研究领域：Bioactive Compounds and Antitumor Agents、Piperaceae Chemical and Biological Studies、Phytochemicals and Medicinal Plants

Toads produce potent toxins, named bufadienolides, to defend against their predators. Pharmacological research has revealed that bufadienolides are potential anticancer drugs. In this research, we reported nine bufadienolides from the eggs of the toad Bufo bufo gargarizans, including two new compounds ( 1 and 3 ). The chemical structures of 1 and 3, as well as of one previously reported semisynthesized compound ( 2 ), were elucidated on the basis of extensive spectroscopic data interpretation, chemical methods, and X-ray diffraction analysis. Compound 1 is an unusual 19-norbufadienolide with rearranged A/B rings. A biological test revealed that compounds 2 and 4 – 8 showed potent cytotoxic activities toward human melanoma cell line SK-MEL-1 with IC 50 values less than 1.0 μM. A preliminary mechanism investigation revealed that the most potent compound, 8, could induce apoptosis via PARP cleavage, while 5 and 6 significantly suppressed angiogenesis in zebrafish. Furthermore, an in vivo biological study showed that 5, 6, and 8 inhibit SK-MEL-1 cell growth significantly.