Recyclization of 2-iminocoumarin-3-carbonitriles with 2-aminothiobenzamide: a new synthetic route to substituted 2-(2-iminocoumarin-3-yl)quinazoline-4(3H)-thiones

The reaction of 2-aminothiobenzamide with either 2-iminocoumarin-3-carbonitrile or 2-iminocoumarin-3-thiocarboxamides has been studied. It has been established that in both cases, 2-(2-iminocoumarin-3-yl)quinazoline-4(3H)-thiones are formed as the result of a two-step procedure. The reactions of 2-(2-iminocoumarin-3-yl)quinazoline-4(3H)-thiones with arylamines and alkylating agents have been studied.