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Methyl 6-O-, 3-O- and 2-O-(2'-hydroxypropyl)-α-D-glucopyranosides (4,8, and 12) were synthesized starting from methyl 2,3,4-tri-O-benzyl-α-D-glucopyranoside (1), methyl 4,6-O-benzylidene-α-D-glucopyranoside (5), and methyl 3-O-benzyl-4,6-O-benzylidene-D-glucopyranoside (9), respectively. Overall yields were 88%, 6% and 26% of 4, 8 and 12, respectively, with the 2-ether (12) being crystalline and the 3-ether (8) a single diastereomer.

Esterification of L-ascorbic acid in concentrated sulfuric acid with 0.33 moles of gallic acid gave a 90% yield of a 2:5 mixture of L-ascorbyl 5- and 6-gallate esters. The 6-gallate ester (1) was purified from the 5-gallate ester (2) by fractional crystallization in 40% yield. Three other aromatic derivatives of L-ascorbic acid also were prepared. The order of antioxidant activities of the L-ascorbyl derivatives determined by thiobarbituric acid number in methyl linolenate at 37 °C was as follows: 6-gallate (1) > 6-(3',4' -dihydroxy)benzoate (3) = 6-(4' -hydroxy)phenyl ether (4) >6-(4' methoxy)phenyl ether (5).