THE STRUCTURE OF DIMETHYLCROCETIN

The structure of dimethylcrocetin (DMCRT), prepared by alkaline hydrol ysis in methanol of the glucosidic carotenoids extracted from the stig mata of the Crocus sativus L. flowers, has been determined. The molecu le has the all-trans configuration and is planar forming a long conjug ated system. The C-O bond length values of the two ester groups are sh ortened as expected. The compound (C11H14O2)(2) crystallizes in the or thorhombic space group Pbcn with a = 12.5907(7), b = 7.5639(5) and c = 21.963(2)Angstrom. Dimethylcrocetin has characteristic Infrared absor ptions at 1697 cm(-1) v (C=O) and 1229 cm(-1) v (C-O) and characterist ic Raman vibrational modes at 1542 cm(-1) v (C=C) and 1166 cm(-1) v (C -C).