The preparation of 6-chloro-2-iodo-9-tetrahydropyranylpurine (2), was achieved in three high yield steps from 6-chloropurine. This derivative was then selectively substituted at C-6 by reaction with a benzylthiol to give 3, a versatile intermediate for the synthesis of 2, 6, 9- trisubstituted purines. Reaction of 3 in palladium-catalyzed cross-coupling reactions,(including Sonogashira coupling at room temperature), as well as nucleophilic ...
