Bromination at C-5 of Pyrimidine and C-8 of Purine Nucleosides with 13-Dibromo-55-dimethylhydantoin

摘要

Treatment of the protected and unprotected nucleosides with 1,3-dibromo-5,5- dimethylhydantoin in aprotic solvents such as CH2Cl2, CH3CN, or DMF effected smooth bromination of uridine and cytidine derivatives at C-5 of pyrimidine rings as well as adenosine and guanosine derivatives at C-8 of purine rings. Addition of Lewis acids such as trimethylsilyl trifluoromethanesulfonate enhanced efficiency of bromination.