First syntheses of disaccharides by use of cycloaddition in a key step
Abstract
O-α-D-altrosyl-(1 → 3)-1,2;5,6-di-O-isopropyli-dene-α-D-glucofuranose, and its O-α-L-altrosyl and O-β-L-altrosyl analogues have been prepared in 35, 42, and ca. 38% yields from the products of the cycloaddition of butyl glyoxylate to 3-O-(buta-1,3-dienyl)-1,2;5,6-di-O- iso-propylidene-β-glucofuranose.