A Study on 4-(3/4-Carboxyphenyl)-4,5-Dihydro-1H-1,2,4-Triazol-5-Ones

O. Gursoy Kol and H. Yuksek*

Department of Chemistry, Faculty of Science and Education, Kafkas University, Kars (Turkey).

A series of 3-alkyl(aryl)-4-(3/4-carboxyphenyl)-4,5-dihydro-1H-1,2,4-triazol-5-ones (2, 3) were obtained from the reactions of ester ethoxycarbonylhydrazones (1) with 3-aminobenzoic acid and 4-aminobenzoic acid, respectively. The chemical structures of the compounds were elucidated by IR, 1H NMR, 13C-NMR and UV spectral data. The synthesized compounds were analyzed for their in vitro antioxidant activities in three different methods including reducing power, free radical scavenging and metal chelating activity. In addition, the compounds 2 and 3 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents. The half-neutralization potential values and the corresponding pKa values were determined for all cases.

4;5-Dihydro-1H-1;2;4-triazol-5-one; Schiff base; antioxidant activity; potentiometric titrations