New access to thiazolo[4,5-d]pyrimidine derivatives

4-Amino-5-bromo-2-substituted-aminopyrimidines are readily obtained from the newly prepared 5-bromo-2,4-dichloro-6-methylpyrimidine by sequential treatment with ethanolic ammonia and secondary amines. These compounds were successfully reacted with various isothiocyanates in the presence of sodamide in DMF to form the new thiazolo[4,5-d] pyrimidine derivatives.