SYNTHESIS OF NUCLEOSIDE ANALOG

摘要

PROBLEM TO BE SOLVED: To provide an improved method for synthesizing nucleoside having lowα:βanomer ratio. SOLUTION: In this method for preparing a protected furanosyl halide, e.g. an analog of 2',3'-O-alkylidene nucleoside, a 2',3'-O-alkylidene furanosyl halide is made to carry out a coupling reaction with a properly protected heterocyclic ring having a nitrogen of a ring capable of forming a covalent bond with an anomer carbon of a furanose or an analog of furanose, in a nucleophilic polar solvent under the presence of a strong base.