Stereospecific fluorination of 1,3,5-tri-O-benzoyl-#alpha#-D-ribofuranose-2-sulfonate esters: preparation of a versatile intremediate for synthesis of 2'-[~18F]-fluoro-arabinonucleosides

摘要

A detailed investigation on fluorination of 1,3,5-tri-O-benzoyl-#alpha#-D-ribofuranose-2-sulphonate esters is reported. Various combinations of sulfonate esters, fluorinating agents and solvents were evaluated in this study. Organic ammonium fluoride, in particular n-Bu_4NF, was found to be better fluorinating agent than inorganic fluoride, and 1,3,5-tri-O-benzoyl-#alpha#-D-ribofuranose-2-trifluoromethylsulphoante ester appeared to the best substrate. The developed methodis suitable for stereospecific (arabino) incorporation of radifluorine (~18F) into the sugar moiety.