Terpenoids and hexenes from the leaves of Crataegus pinnatifida.

Crataegus pinnatifida have long been used in traditional Chinese medicine and European herbal medicine, and are widely consumed as food, in the form of juice, drink, jam and canned fruit. Four new compounds, a sesquiterpene and its glycoside (1-2), two monoterpene glycosides (3-4), together with eight known compounds (5-12), were isolated from the leaves of C. pinnatifida. Their structures were elucidated as (5Z)-6-[5-(2-hydroxypropan-2-yl)-2-methyltetrahydrofuran-2-yl]-3-methylhexa-1,5-dien-3-ol (1), (5Z)-6-[5-(2-O-β-d-glucopyranosyl-propan-2-yl)-2-methyl tetrahydrofuran-2-yl]-3-methylhexa-1,5-dien-3-ol (2), 5-ethenyl-2-[2-O-β-d-glucopyranosyl-(1″→6')-β-d-glucopyranosyl-propan-2-yl]-5-methyltetrahydrofuran-2-ol (3), 4-[4β-O-β-d-xylopyranosyl-(1″→6')-β-d-glucopyranosyl-2,6,6-trimethyl-1-cyclohexen-1-yl]-butan-2-one (4), (Z)-3-hexenyl O-β-d-glucopyranosyl-(1″→6')-β-d-glucopyranoside (5), (Z)-3-hexenyl O-β-d-xylopyranosyl-(1″→6')-β-d-glucopyranoside (6), (Z)-3-hexenyl O-β-d-rhamnopyranosyl-(1″→6')-β-d-glucopyranoside (7), (3R,5S,6S,7E,9S)-megastiman-7-ene-3,5,6,9-tetrol (8), (3R,5S,6S,7E,9S)-megastigman-7-ene-3,5,6,9-tetrol9-O-β-d-glucopyranoside (9), (6S,7E,9R)-6,9-dihydroxy-4,7-megastigmadien-3-one 9-O-[β-d-xylopyranosyl-(1″→6')-β-d-glucopyranoside] (10), Linarionoside C (11), and (3S,9R)-3,9-dihydroxy-megastigman-5-ene 3-O-primeveroside (12), using a combination of mass spectroscopy, 1D and 2D NMR spectroscopy and chemical analysis. Cytotoxicity of the new compounds was assayed against selected human glioma (U87) cell lines.