Domino synthesis of quinazolin-4-yl thioureido alkanoates

A simple convenient protocol for the synthesis of methyl 2-[3-(2-(substituted phenyl)quinazolin-4-yl)thioureido] alkanoates is described. It involves the domino reaction of various amino acid esters with imidoylisothiocyanates in ethyl acetate to afford quinazoline thiourea derivatives in excellent yields. Short reaction time, mild condition, simple work up, high yields, and pure products are the major advantages of this protocol. The number of isolated pure compounds from this simple protocol is 24. The starting imidoyl isothiocyanates were prepared from the corresponding benzanilides and were purified by flash chromatography.