Norcolocynthenins A and B, two cucurbitane 3-nor-Triterpenoids from Citrullus colocynthis and their cytotoxicity.
Two novel cucurbitane 3-nor-triterpenoids, named norcolocynthenins A (1) and B (2), were isolated from the fruits of Citrullus colocynthis. The structures including their absolute configurations were determined by extensive spectroscopic analyses and theoretical calculations. Compound 1 features an unprecedented 5/6/6/5-fused ring system while compound 2 possesses a rare lactone moiety at modified ring A. Compounds 1 and 2 showed significant cytotoxic activity against human cancer cell lines of HL-60 (IC50 = 8.32, 6.49 μM) and PC-3 (IC50 = 31.26, 13.42 μM). The plausible biosynthetic pathway of compounds 1 and 2 via a key enzymatic Baeyer-Villiger reaction is proposed.
['Liu|Yushuang|Y|', 'Zhang|Lu|L|', 'Xue|Jingjing|J|', 'Wang|Kaibo|K|', 'Hua|Huiming|H|', 'Yuan|Tao|T|']
D000818:Animals D065986:Citrullus colocynthis D006027:Glycosides D006801:Humans D008297:Male D015394:Molecular Structure D051381:Rats D017207:Rats, Sprague-Dawley D014315:Triterpenes
Citrullus colocynthis Cytotoxicity Theoretical calculations Cucurbitane nortriterpenoid