Collect. Czech. Chem. Commun. 1994, 59, 222-226

Synthesis of Some 1,2,4-Triazolo[4,3-c]quinazolines Based on 4-Quinazolylthiosemicarbazides

Katarína Špirková, Štefan Stankovský and Miloslava Dandárová

Department of Organic Chemistry, Slovak Technical University, 812 37 Bratislava, Slovak Republic


The paper describes the cyclization reactions of substituted 1-(4'-quinazolyl)-4-phenylthiosemicarbazides (Ia - Ie). The thermal intramolecular cyclization gives 2H-1,2,4-triazolo[4,3-c]quinazoline-3-thiones (IIa - IId). Heating of I with HgO gives 3-anilino-1,2,4-triazolo[4,3-c]quinazolines (IIIa - IIIe). The IR and 1H NMR spectra of the compounds synthesized are presented.