A new class of aminopyrazolones, aminoisoxazolones, aminopyrimidinones, and thioxopyrimidinones were synthesized from Michael adduct, ethyl‐3,4‐diaroyl‐2‐cyanobutyrate, on reaction with different nucleophiles, hydrazine hydrate, hydroxylamine hydrochloride, and urea derivatives. J. Heterocyclic Chem., (2009).