Synthesis of methyl (R)- and (S)-[ 18 O]phosphorothioates and determination of the absolute configuration at phosphorus of the diastereoisomers of adenosine 5′-(1-thiotriphosphate)

A general route for the synthesis of enantiomeric [18O]phosphorothioate esters of known absolute configuration has been developed, and isomer A of adenosine 5′-(1-thiotriphosphate) shown to have the (S)-configuration at Pα.