ACYLATED CYANIDIN 3-RUTINOSIDE-5,3'-DIGLUCOSIDE FROM THE PURPLE-RED FLOWER OF LOBELIA ERINUS

A new acylated anthocyanin was isolated from the purple-red flowers of Lobelia erinus cv 'Rosamond'. Its structure was elucidated to be cyan idin 6-0-(4-O-trans-p-coumaryl-alpha-L-rhamnopyranosyl) de)-3'-O(6-O-t rans-caffeyl-beta-D-glucopyranoside) by spectroscopic evidence. The th ree dimensional structure of this pigment was suggested from the obser vation of difference negative NOE spectrum analysis that cyanidin (chr omophore) and caffeic acid (intracopigment) occupy a folding conformat ion as a stacking structure.