SYNTHESIS OF GLYCOSYL PHOSPHATES FROM SUGAR ORTHO ESTERS: FORMATION OF BIS(2,3,4,6-TETRA-O-ACETYL-β-D-GLUCOPYRANOSYL) PHOSPHATE, AND THE EFFECT OF SOLVENTS ON THE SYNTHESIS OF β-D-GLUCOPYRANOSYL PHOSPHATE

Article abstract of DOI:10.1016/S0008-6215(00)85614-1

Reaction of exo-3,4,6-tri-O-acetyl-1,2-O-(tert-butyl orthoacetyl)-α-D-glucopyranose with phosphoric acid and phosphorus pentaoxide in oxolane gave 2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl phosphate.Treatment of the reaction mixture with aqueous lithium hydroxide gave the expected β-D-glucopyranosyl phosphate.However, neutralization with ammonium hydroxide gave exclusively the phosphoric diester, namely, bis(2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl) phosphate.Formation of the diester was traced to the phosphorus pentaoxide in the initial reaction-mixture.A study of solvents showed that phosphorylation of the ortho ester proceeds rapidly in a variety of ethers and N,N-dimethylamides.