2,3,4-Tri-O-acetyl-alpha-D-glucuronic Acid Methyl Ester → methyl 2,3,4-tri-O-acetyl-1-O-[p-[(E)-2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl)-propenyl]-benzoyl]-D-glucopyranuronate

Participants

Reaction Steps

A solution of 3.4 g of methyl 2,3,4-tri-O-acetyl-α-D-glucopyranuronate in 40 ml of pyridine was reacted at 0° C. with a solution of p-[(E)-2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl)-propenyl]-benzoyl chloride in 70 ml of ether. The mixture was stirred at room temperature overnight, evaporated to dryness and the residue was chromatographed on silica gel with hexane/ethyl acetate. There was obtained methyl 2,3,4-tri-O-acetyl-1-O-[p-[(E)-2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthyl)-propenyl]-benzoyl]-D-glucopyranuronate as a mixture of the β- and α-anomers (ca 4:1). Melting point 149°-150° C. (from ethanol); [α]D25 =3° (c=1 in chloroform).

Provenance & Evidence