A New Flavone C-glycoside from Citrullus colocynthis

Objective To study the chemical constituents of Citrullus colocynthis. Methods The chemical constituents were isolated and purified by column chromatography on silica gel and Sephadex LH-20 and recrystallization as well. NMR spectra and physicochemical property were characterized for structural identification. Results Eleven compounds were isolated and identified as β-sitosterol (1), α-spinasterol-3-O-β-D-glucopyranoside (2), α-spinasterone (3), bis (2-ethylhexyl) phthalate (4), p-hydroxybenzoic acid (5), 6-C-p-methylbenzoylvitexin (6), dihydrocucurbitacin E (7), cucurbitacin E (8), dihydro-epi-iso-cucurbitacin D (9), dihydroisocucurbitacin B-25-acaetate (10), and cucurbitacin E 2-O-β-D-glucopyranoside (11). Conclusion Compound 6 is a novel compound. Compounds 1-5, 7, 9, and 10 are isolated from C. colocynthis for the first time.