Porcine Liver Esterase-Catalyzed Hydrolysis of Methyl Tri-O-acetyl-β-D-arabinopyranoside, Methyl Tri-O-acetyl-β-D-ribopyranoside and Methyl Tri-O-acetyl-β-D-ribofuranoside

Investigation of acetyl migrations in furanosides

Standard reaction conditions for the desilylation of acetylated furanoside (riboside, arabinoside and xyloside) derivatives facilitate acyl migration. Conditions which favour intramolecular and intermolecular mechanisms have been identified with intermolecular transesterifications taking place under mild basic conditions when intramolecular orthoester formations are disfavoured. In acetyl ribosides, acyl migration could be prevented when desilylation was catalysed by cerium ammonium nitrate.

A convenient preparation of 1,2,3-tri-O-acetyl-beta-D-ribofuranose by enzymatic regioselective 5-O-deacetylation of the peracetylated ribofuranose

The lipase from Candida rugosa (Sigma) was used to catalyze the regioselective deacetylation at the 5-position of 1,2,3,5-tetra-O-acetyl-beta-D-ribofuranose on a preparative scale. Enzymatic deacetylation provides a convenient one-step preparation of 1,2,3-tri-O-acetyl-beta-D-ribofuranose.