Abstract
Six new stable anthocyanins, named ternatin A1, A2, B1, B2, D1 and D2, were isolated from the blue flowers of Clitoria ternatea L.. The structures of two common components prepared from alkaline deacylation of ternatin mixture were determined as E-4-p-coumaryl β-D-glucoside(1) and delphinidin 3,3',5'-tri-β-D-glucoside(2), respectively. Based on the HPLC analysis of deacylated products and FAB-MS data, the structure of each ternatin was estimated. Thus the structures of ternatin D1, A1 and A2 were completely identified as 3, 4 and 5 by PMR, CMR and DIFNOE spectroscopies. The 3',5'-side chains of 3 and 4 had high symmetry forms more than that of 5. The exceptional color stability of ternatins in a neutral solution is attributed to the intramolecular copigmentation(stacking) between delphinidin nucleus and p-coumaryl moieties of 3',5'-side chains.
