New caryophyllene-type sesquiterpene and flavonol tetraglycoside with sixteen known compounds from sword bean (Canavalia gladiata)

Abstract

Eighteen compounds including new caryophyllene-type sesquiterpene and flavonol tetraglycoside were purified and isolated from sword beans (Canavalia gladiata). Two new compounds, (Z,1R,7S,9S)-7-hydroxy-11,11-dimethyl-8-methylenebicyclo[7.2.0]undec-4-ene-4-carboxylic acid (2) and kaempferol-7-O-α-l-dirhamnopyranosyl(1 → 2;1 → 6)-O-β-d-glucopyranosyl(1 → 2)-O-α-l-rhamnopyranoside (9), were identified. Other known compounds including methyl gallate (1), (2S,3S,4E,8E)-2-aminooctadeca-4,8-diene-1,3-diol 1-O-β-d-glucopyranoside (3), (2S,3S,4E,8Z)-2-aminooctadeca-4,8-diene-1,3-diol 1-O-β-d-glucopyranoside (4), lupeol (5), trilinolein (6), 1,6-di-O-galloyl β-d-glucopyranoside (7), N-(2-methoxybenzoyl)homoserine (8), dihydrophaseic acid (10), dillenetin (11), kaempferol-7-O-[2-O-β-d-glucopyranosyl-6-O-α-l-rhamnopyranosyl]-α-l-rhamnopyranoside (12), canavalioside (13), kaempferol-3-O-[2-O-β-d-glucopyranosyl-6-O-α-l-rhamnopyranosyl]-β-d-glucopyranoside (14), kaempferol-3-O-(2,6-O-α-l-dirhamnopyranosyl)-β-d-glucopyranoside (15), kaempferol-3-O-rutinoside (16), gladiatoside A₁ (17), and gladiatoside B₁ (18) were identified. The chemical structures of these compounds were determined by ESI-MS and NMR analyses.

Keywords: Canavalia galidata; Cerebioside; Flavonoid tetraglycoside; Sesquiterpenoic acid; Sword bean.