SYNTHESIS OF 2′-DEOXY-2′-FLUORO- 1-β- d -ARABINOFURANOSYL URACIL DERIVATIVES: A METHOD SUITABLE FOR PREPARATION OF [18F]-LABELED NUCLEOSIDES

N-glycosylation of 2,4-bis-O-(trimethylsilyl)-pyrimidine bases with 2-deoxy-2-fluoro-3,5-di-O-benzoyl-1-(Br, OBz)-α-d-arabinose derivatives are reported. 1-Bromo-arabinose provides high yield and a favorable anomeric ratio (β/α) of pyrimidine nucleoside in either MeCN or CH2Cl‒CH2Cl. This method should be suitable for the synthesis of 2′-deoxy-2′-[18F]fluoro-1-β-d-arabinofuranosyluracil derivatives.