Selective Biocatalytic Acylation Studies on 5′-<i>O</i>-(4,4′-Dimethoxytrityl)-2′,3′-Secouridine: An Efficient Synthesis of UNA Monomer
作者:Sunil K. Singh、L. Chandrashekhar Reddy、Smriti Srivastava、Carl E. Olsen、Yogesh S. Sanghvi、Niels Langkjær、Jesper Wengel、Virinder S. Parmar、Ashok K. Prasad
DOI:10.1080/15257770.2012.734424
日期:2012.12
Lipozyme (R) TL IM (Theremomyces lanuginosus lipase immobilized on silica) in toluene catalyzes the acylation of the 2 '-OH over the 3 '-OH group in 5 '-O-(4,4 '-dimethoxytrityl)-2 ',3 '-secouridine (5 '-O-DMT-2 ',3 '-secouridine) in a highly selective fashion in moderate to almost quantitative yields. The turn over during benzoyl transfer reactions mediated by vinyl benzoate or benzoic anhydride was faster than in acyl transfer reactions with vinyl acetate or C1 to C5 acid anhydrides; except in the case of butanoic anhydride. The 2 '-O-benzoyl-5 '-O-DMT-2 ',3 '-secouridine obtained by Lipozyme (R) TL IM catalyzed benzoylation of 5 '-O-DMT-2 ',3 '-secouridine was successfully converted into its 3 '-O-phosphoramidite derivative in satisfactory yield, which is a building block for the preparation of oligonucleotides containing the uracil monomer of UNA (unlocked nucleic acid).