Design and racemic synthesis of conformationally restricted carbocyclic pyrimidine nucleoside analogs based on the structure of the L-nucleoside residue in heterochiral DNA

Abstract

Carbocyclic pyrimidine nucleoside analogs which have restricted glycosidic conformation at χ 180°were designed, based on the conformational features of the L-nucleotide residue in heterochiral DNA, and synthesized. The synthesis of (±)-carbocyclic 6,6'-O-cyclo-2'-deoxyuridine was achieved via bromination and subsequent intra-molecular cyclization of carbocyclic 6'β-hydroxy-2'-deoxyuridine. (±)-Carbocyclic 6,6'-O-cyclo-2'- deoxycytidine was synthesized from protected carbocyclic 6,6'-O-cyclo-2'- deoxyuridine via the 4-triazole intermediate.