7-Polyacylated delphinidin 3,7-diglucosides from the blue flowers of Leschenaultia cv. Violet Lena

The triacyl anthocyanins, Leschenaultia blue anthocyanins 1 and 2 (LBAs 1 and 2) were isolated from the blue flowers of Leschenaultia R. Br. cv. Violet Lena (Goodeniaceae), in which LBA 1 was present as a dominant pigment. The structure of LBA I was elucidated to be delphinidin 3-O-[6-O-(malonyl)-beta-D-glucopyranoside]-7-O-[beta-D-(4-O-(beta-O-(4-O-(P-D-glucopyranosyl)-trans-caffeoyl)-beta-D-glueopyranosyl)-trans-caffeoyl)-beta-D-glucopyranoside] by application of chemical and spectroscopic methods. Since LAB 2 was isolated in small amount, its structure was tentatively assigned as either delphinidin 3-(malonylglucoside)-7-[(glucosyl-p-coumaroyl)-(glucosylcaffeoyl)glucoside] or delphinidin 3-(malonyl-gluco side)-7-[(glucosyl-caffeoyl)(glucosyl-p-coumaroyl)-glucoside]. This is the first report of the occurrence of 7-polyacylated anthocyanins in the family of Goodeniaceae, although others have been found in the families of the Ranunculaceac, Campanulaceae, and Compositae. Moreover, delphinidin 3-glycoside-7-di-(glucosylcaffeoyl)-glucoside has been reported only in the flowers of Platycodon grandflorum (Campanulaceae). From a chemotaxonomical viewpoint, the Goodeniaceae may be closely related to the Campanulaceae. (c) 2006 Elsevier Ltd. All rights reserved.