Evaluation of the anti-inflammatory and analgesic effects of Cu(II) and Zn(II) complexes derived from 2-(naphthalen-1-yloxy)-N′-(1-(pyridin-2-1)ethylidene) acetohydrazide

New Cu(II) and Zn(II) complexes of 2-(naphthalen-1-yloxy)-N'-(1-(pyridin-2-yl)ethylidene) acetohydrazide (HA2PNA) have been prepared and characterized by elemental analyses, spectral (IR, UV-visible, ESR and H-1 NMR) as well as magnetic and thermal measurements. According to the data, the complexes assigned the formulae: [Cu(A2PNA)(2)]H2O and [Zn(A2PNA)(OAc)(H2O)], respectively. IR data revealed that the ligand acts as before ONN and after morever ONN mononegative tridentate via deprotonated carbonyl oxygen (=C-O-) and both (C=N)(imine) and (C=N)(pyridine) nitrogen atoms. The bond lengths, bond angles, HOMO, LUMO, dipole moment and charges on the atoms have been calculated by using density functional theory (DFT) at B3LYP level with 6-31G and 6-31G(d,p) basis sets to confirm the geometry of the ligand and the investigated complexes. Also, the kinetic parameters were determined for each thermal degradation stage of the complexes using Coats-Redfern and Horowitz-Metzger methods. Moreover, the complexes have been tested for anti-inflammatory and analgesic activity in rat model of collagen adjuvant arthritis and compared with piroxicam. All the compounds showed a significant anti-inflammatory and analgesic effect versus piroxicam. (C) 2013 Elsevier B.V. All rights reserved.