Anthocyanins from fruits of Rubus pinnatus and Rubus rigidus

The same anthocyanins, cyanidin 3-(6″-O-α-rhamnopyranosyl-β-glucopyranoside) (1), and cyanidin-3-O-β-glucopyranoside (2), were isolated from extracts of red fruits of Rubus pinnatus Willd. and purple-black fruits of Rubus rigidus Sm. using Amberlite XAD-7 column chromatography, Sephadex LH-20 gel filtration and preparative HPLC. Their structures were elucidated by a combination of chromatography, homo- and heteronuclear NMR techniques. The relative amounts of 1 and 2 in R. rigidus were 59.4% and 40.6%, respectively, while in R. pinnatus, the relative amounts were 58.6% and 41.4%, respectively.