Abstract 2-Alkyl and 2-aryl-3-(phenylamino)quinazolin-4(3H)-ones 4a–h were synthesized in a one-potthree-component condensation of an isatoic anhydride 1a–h, ethyl or methyl ortho ester and phenylhydrazine in the presence of KAl(SO4)2·12H2O (alum) as a nontoxic, reusable, inexpensive and easily available catalyst. The synthesis was conducted undermicrowaveirradiation or classical heating. Products