Synthesis, acidity and antioxidant properties of some novel 3,4-disubstituted-4,5-dihydro-1H-1,2,4-triazol-5-one derivatives

Alkan M., Yuksek H., Gursoy-Kol O., Calapoglu M.

MOLECULES, vol.13, no.1, pp.107-121, 2008 (Peer-Reviewed Journal) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 13 Issue: 1
  • Publication Date: 2008
  • Doi Number: 10.3390/molecules13010107
  • Journal Name: MOLECULES
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.107-121
  • Keywords: 4,5-Dihydro-1H-1,2,4-triazol-5-ones, schiff base, acetylation, antioxidant activity, pK(a), potentiometric titrations, GIAO NMR CALCULATIONS, NONAQUEOUS MEDIUM TITRATIONS, 4,5-DIHYDRO-1H-1,2,4-TRIAZOL-5-ONE DERIVATIVES


3-Alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones 2a-g reacted with 4-diethylaminobenzaldehyde to afford the corresponding 3-alkyl(aryl)-4-(4-diethylaminobenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 3a-g. The acetylation reactions of compounds 3a-e were investigated and compounds 4a-e were thus obtained. The new compounds were characterized using IR, H-1-NMR, C-13-NMR, UV and MS spectral data. In addition, the newly synthesized compounds 3a-g were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents such as isopropyl alcohol, tert-butyl alcohol, acetone and N,N-dimethylformamide (DMF), and the half-neutralization potential values and the corresponding pK(a) values were determined for all cases. Moreover, 3 and 4 type compounds were also screened for their antioxidant activities.