Syntheis of Zeaxanthin- and Cryptoxanthin-b-D-glucopyranosides

Abs t ract -β-Glucosidation of (3R)-3-hydroxy-β-ionone (6) was achieved in a reasonable yield by use of tetra-O-benzoyl-α-Dglucopyranosyl bromide (8c) as a glycosyl donor and silver triflate as an activator.The resulting glucoside (9) was transformed into the β-apo-12'-carotenal (18), which was condensed with the Wittig salt (19) or ( 20) to provide zeaxanthin-mono-β-D-glucopyranoside (3) or cryptoxanthin-β-D-glucopyranoside (4).