Porcine liver esterase-catalyzed hydrolysis of methyl tri-O-acetyl-beta-D-arabinopyranoside, methyl tri-O-acetyl-beta-D-ribopyranoside and methyl tri-O-acetyl-beta-D-ribofuranoside

Methyl 2,3,4-tri-O-acetyl-beta -D-arabinopyranoside (1), methyl 2,3,4-tri-O -acetyl-beta -D-ribopyranoside (2), and methyl 2,3,5-tri-O-acetyl-beta -D-r ibofuranoside (3) were deacetylated in porcine liver esterase-catalyzed rea ctions. Triacetate 1 gave methyl 3,4-di-O-acetyl-beta -D-arabinopyranoside in 70%, preparative yield while the regioselectivities found for the substr ates 2 and 3 were substantially lower. Both the Michaelis constant and maxi mum rate were calculated for deacetylation of 1, 2, and 3. The results were interpreted using an active site model for the esterase proposed by Jones.