C2-Blocked N- Pyrimidin-3-yl thioimidates with One-Nitrogen Fragments

Cyclization of C2-Blocked N-(Pyrimidin-3-yl)thioimidates with One-Nitrogen Fragments 

Photolysis of the 2-methyl-quinazolin-3-yl thioimidate 19 in the presence of butylamine produced an intricate mixture of products from which the 

-Diaminopyrimidines fused to a number of heterocycles (35) were also cyclized with one-carbon inserting agents to the corresponding hetero-cyclo-l,2,4-triazolo[l,5-c]pyrimidines 36 (75M1111 81JHC43 97JIC27). 

Diethyl oxalate functioned as one-carbon rather than two-carbon cyclizing agent with the diamino-heterocyclopyrimidines 37 to give the triazo-lopyrimidines 38. Diethyl malonate, ethyl acetoacetate, or ethyl 

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