Synthesis of 2,8-disubstituted 1,2,4-triazolo[5,1-i]purines

This paper describes the preparation of 2-aryl-8-fluorobenzyl-1,2,4-triazolo5,1-i]purines 2 , starting from 2-aryl-7,8-diamino-1,2,4-triazolo1,5-c]pyrimidines 9 . Our synthetic procedure represents the first example of a feasible approach for the synthesis of 2,8-disubstituted triazolo5,1-i]purines. New syntheses of 5-amino-3-arylpyrimido5,4-e]1,2,4-triazines 12 and 8-fluorobenzyl-6-hydrazinopurines 15 are also reported.