Abstract A general route to 1, 2, 4-trisubstituted pyrimidines is described in one to three steps from a common key precursor, diazadienium iodide 2. An efficient preliminary [4+ 2] cyclocondensation reaction between the azabutadiene building block 2 and various iso (thio) cyanates constitutes an original construction of the pyrimidine skeleton. Subsequent structural modifications on the heterocycle allow the elaboration of a 1-substituted ...
