Condensation reactions of guanidines with bis-electrophiles: formation of highly nitrogenous heterocycles

2-Amino-1,4-dihydropyrimidines were reacted with bis-electrophiles to produce novel fused bipyrimidine, pyrimidoaminotriazine, and pyrimidosulfonamide scaffolds. In addition, a quinazoline library was constructed using a guanidine Atwal–Biginelli reaction with 1-(quinazolin-2-yl)guanidines. The product heterocycles have novel constitutions with high nitrogen atom counts and represent valuable additions to screening libraries for the discovery of new modulators of biological targets.