Acylated anthocyanins from leaves of the water lily, Nymphaea x Marliacea

Three anthocyanins have been isolated from the leaves of the water lily, Nymphaea x marliacea. Even though the lability of the two major anthocyanins was high, especially the linkage between the acetic acid and the galactose moieties, it was possible by means of home-and heteronuclear two-dimensional NMR techniques and electrospray mass spectrometry to give the full structures of the novel pigments; delphinidin 3-O-(2 ''-O-galloyl-6 ''-O-acetyl-beta-galactopyranoside) (69%) and delphinidin 3-O-(6 ''-O-acetyl-beta-galactopyranoside) (24%). The third anthocyanin (1.5%) was identified as delphinidin 3-O-beta-galactopyranoside. Diacylation including gallic acid as one acyl moiety has previously not been reported for any flavonoid, and this is the first report of a 2 '',6 ''-diacylated anthocyanin involving an aliphatic acid. (C) 1997 Elsevier Science Ltd.