Synthesis and biological activities of some novel triazoloquinazolines and triazinoquinazolines containing benzenesulfonamide moieties

Abstract

The reactivity of methyl-2-isothiocyanatobenzoic acid 2 towards nitrogen nucleophiles was investigated. When compound 2 was reacted with sulfanilamide and/or sulfacetamide the thioureido derivatives 3 and 4 were obtained. Refluxing of compound 3 or 4 with hydrazine hydrate in ethanol afforded the N-aminoquinazoline derivatives 5 and 6, respectively. When compound 5 was reacted with aromatic aldehydes in ethanol, the novel Schiff's bases 7-9 were produced. In a similar manner, aromatic aldehydes were reacted with compound 6 in acetic acid containing fused sodium acetate to furnish the triazoloquinazoline derivatives 10-13. Also, triazoloquinazoline derivative 14 was obtained via reaction of compound 6 with acetic anhydride. In addition, the corresponding triazinoquinazoline derivative 16 was obtained via reaction of compound 6 with ethyl chloroacetate. The triazoloquinazoline 19 was obtained in good yield via the reaction of 6 with diethyloxalate. Moreover, some of the newly synthesized compounds showed good antipyretic and anti-inflammatory activities.