Anthocyanins with unusual furanose sugar (apiose) from leaves of Synadenium grantii (Euphorbiaceae)

Four anthocyanins, cyanidin 3-O-(2″-(5‴-(E-p-coumaroyl)- β-apiofuranosyl)-β-xylopyranoside)-5-O-β-glucopyranoside, cyanidin 3-O-(2″-(5‴-(E-p-coumaroyl)-β-apiofuranosyl)-β- xylopyranoside), cyanidin 3-O-(2″-(5‴-(E-caffeoyl)-β- apiofuranosyl)-β-xylopyranoside) and cyanidin 3-O-(2″-(5‴-(E- feroyl)-β-apiofuranosyl)-β-xylopyranoside) were isolated from leaves of African milk bush, (Synadenium grantii Hook, Euphorbiaceae) together with the known cyanidin 3-O-β-xylopyranoside-5-O-β-glucopyranoside and cyanidin 3-O-β-xyloside. The four former pigments are the first reported anthocyanins containing the monosaccharide apiose, and the three 5‴-cinnamoyl derivative-2″-(β-apiosyl)-β-xyloside subunits have previously not been reported for any compound. © 2010 Elsevier Ltd.