Hafnium(IV) triflate as a potent catalyst for selective 1-O-deacetylation of peracetylated saccharides.

An efficient method for selective anomeric deacetylation of peracetylated mono-, di-, and trisaccharides has been developed by using 2 mol% Hf(OTf)4 as catalyst in acetonitrile. Employment of ultrasonic irradiation could significantly accelerate the reaction rate. Mechanistic study confirmed the hydrolysis nature of this reaction, and NMR experimental data suggested that multiple peracetylated saccharide molecules may ligate to Hf(IV) cation primarily via the anomeric acetate to promote its specific hydrolysis.

Efficient Synthesis of 5-Carboxy-2'-Deoxypyrimidine Nucleoside 5'-Triphosphates.

An efficient P(V)-N activation method for the synthesis of 5-carboxy-2'-deoxyuridine and 5-carboxy-2'-deoxycytidine triphosphates directly from the corresponding phosphoropiperidate precursors has been developed.