Acylated cyanidin 3,7,3′-triglucosides in flowers of × Laeliocattleya cv. Mini Purple and its relatives
文摘
Ten acylated cyanidin 3,7,3′-triglucosides were isolated from the red-purple flowers of × Laeliocattleya cv. Mini Purple as major anthocyanins, along with a known pigment. The occurrence of these pigments was examined in the flowers of its parent species, Laelia pumila and Cattleya walkeriana, by HPLC. These ten pigments were observed in both parents, and FAB-mass measurements gave molecular ions [M]+ at m/z 1459-1669, which were based on acylated cyanidin 3,7,3′-triglucosides with malonic acid, p-coumaric acid, caffeic acid, ferulic acid and glucosylated hydroxycinnamic acids. This was confirmed by the analysis of 1H NMR spectra and results obtained from acid and alkaline hydrolysis. Four new acylated anthocyanin structures (2, 3, 6 and 7) were based on cyanidin 3-O-[6-O-(malonyl)-^6;-d-glucopyranoside]-7-O-[6-O-(acyl-I)-^6;-d-gluocpyranoside]-3′ -O-[6-O-(trans-4-O-(6-O-(acyl-II)-^6;-d-glucopyranosyl)-(acyl-III)-^6;-d glucopyranoside], in which 3 was acylated with p-coumaric acid at acyl-I and -III, and caffeic acid at acyl-II, 6 was acylated with p-coumaric acid at acyl-I and caffeic acid at acyl-II and -III, 7 was acylated with three molecules of caffeic acid and the three acyl groups (acyl I-III) of 2 were composed of one molecule of caffeic acid and two molecules of ferulic acid.
