Multiflorenol

The methanol extract of wax gourd (Japanese name "Tougan"), the fruits of Benincasa hispida COGN. (Cucurbitaceae), was found to show inhibitory activity on the histamine release from rat exudate cells induced by antigen-antibody reaction. Through bioassay-guided separation, four known triterpenes and two known sterols were isolated as active components together with a flavonoid C-glycoside, an acylated glucose, and a benzyl glycoside. Among the active triterpenes and sterols, two triterpenes, alnusenol and multiflorenol, were found to potently inhibit the histamine release.

The compounds of Ainsliaea yunnanensis were isolated and purified by various kinds of column chromatography methods and their structures were determined by spectroscopic data analysis. Twelve compounds were obtained from the petroleum ether of ethanolic extract of A. yunnanensis and elucidated as bauerenyl acetate (1), bauerenol (2), alpha-amyrin (3), psi-taraxasterol (4), beta-amyrin (5), echinocystic acid (6), multiflorenol (7), 3beta-hydroxy-olean-18-ene germanicol (8), 3beta-hexadecanoyl-12-oleanen-11-one (9), fernenol (10), fern-7-en-3beta-ol (11), and lupeol (12). All compounds were isolated from this genus for the first time except compound 1, 3, 5 and 10, and they were all isolated from this plant for the first time.

Benincasa hispida (Thunb.) Cogn. fruits are widely consumed in China and tropical countries. This study identifies three new triterpenoids, 3α,29-O-di-trans-cinnamoyl-D:C-friedooleana-7,9(11)-diene (1), oleanolic acid 28-O-β-d-xylopyranosyl-[β-d-xylopyranosyl-(1→4)]-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside (2), and oleanolic acid 28-O-β-d-glucopyranosyl-(1→3)-β-d-xylopyranosyl-[β-d-xylopyranosyl-(1→4)]-(1→3)-α-l-rhamnopyranosyl-(1→2)-α-l-arabinopyranoside (3), together with 12 known compounds, multiflorenol (4), isomultiflorenyl acetate (5), stigmasterol (6), stigmasterol 3-O-β-d-glucopyranoside (7), α-spinasterol (8), α-spinasterol 3-O-β-d-glucopyranoside (9), β-sitosterol (10), daucosterol (11), arbutin (12), nicotinic acid (13), (+)-pinonesinol (14), and ethyl β-d-glucopyranoside (15). The structures of compounds 1-15 were determined by spectroscopic and chemical methods. All the compounds with the exception of 4, 5, and 9-11 were isolated from B. hispida for the first time. The anticomplement activities of compounds 1-15 were assessed by Mayer's modified method. Compounds 1-15 showed no significant cytotoxic activity against HeLa human cervical, HL-60 human hepatoma, and SMMC-7721 human hepatoma cell lines.