Synthesis of some new spiroquinazoline-4-heterocyclic derivatives

2,3-Dimethyl-3H-quinazoline derivatives 2a,b reacted with malonic acid in the presence of anhydrous ZnCl2 to afford -(4-quinazolinylideneJ acetic acid derivatives 3a,b which then reacted with thionyl chloride to give the corresponding acid chlorides. The acid chlorides reacted with arenes in the presence of AlCl3 to yield substituted 4-quinazolinylideneacetophenones 4a-d. Compounds 4a-d were treated with hydrazine derivatives, hydroxylamine hydrochloride, urea and thiourea to yield the spiro compounds 5a-h, 6a-d and 7a-h, respectively.