Details

Autor(en) / Beteiligte

• Chkirate, Karim
• Fettach, Saad
• Karrouchi, Khalid
• Sebbar, Nada Kheira
• Essassi, El Mokhtar
• Mague, Joel T.
• Radi, Smaail
• El Abbes Faouzi, My
• Adarsh, N.N.
• Garcia, Yann

Titel

Novel Co(II) and Cu(II) coordination complexes constructed from pyrazole-acetamide: Effect of hydrogen bonding on the self assembly process and antioxidant activity

Ist Teil von

• Journal of inorganic biochemistry, 2019-02, Vol.191, p.21-28

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2019

Quelle

MEDLINE

Beschreibungen/Notizen

• In the present study, two pyrazole-acetamide derivatives namely N‑(2‑aminophenyl)‑2‑(5‑methyl‑1H‑pyrazol‑3‑yl) acetamide (L1) and (E)‑N‑(2‑(1‑(2‑hydroxy‑6‑methyl‑4‑oxo‑4H‑pyran‑3‑yl)ethylideneamino)phenyl)‑2‑(5‑methyl‑1H‑pyrazol‑3‑yl) acetamide (L2) have been synthesized and characterized by infrared spectrophotometry (IR), nuclear magnetic resonance spectroscopy (NMR) and electrospray ionization-mass spectrometry (ESI-MS). Two coordination complexes of L1 and L2, namely [Co(L1)2(EtOH)2]·Cl2 (1) and [Cu(L2)]·H2O (2), respectively have been synthesized and characterized by elemental analysis and spectroscopic studies. The solid state structure of these two complexes was established by single crystal X-ray crystallography. In complex 1, the amide O and pyrazole N atoms of two molecules of L1 take part in coordination with octahedral Co(II) ions, the remaining two coordination sites being occupied by two EtOH molecules leading to a N2O4 coordination environment. On the other hand, the imine N atoms, pyrazole N and O atoms of the 2‑hydroxy‑6‑methyl‑4H‑pyran‑4‑one function present in L2 are involved in coordination with Cu(II) ions, resulting in a distorted square planar geometry displaying a N2O4 chromophore, in complex 2. The crystal packing analysis of 1 and 2, revealed 1D and 2D supramolecular architectures respectively, via various hydrogen bonding interactions, which are discussed in the present account. Furthermore, the antioxidant activity of the ligands and their complexes were determined in vitro by 1,1‑diphenyl‑2‑picrylhydrazyl (DPPH), 2,2′‑azino‑bis(3‑ethylbenzothiazoline‑6‑sulphonic acid (ABTS) and ferric reducing antioxidant power(FRAP), showing that the ligands L1 and L2 and complexes 1 and 2 present significant antioxidant activity. [Display omitted] •Synthesis of new pyrazole-acetamide derivatives and two coordination complexes•X-ray single crystal structure description of these complexes•Study the impact of supramolecular bonding on crystal packing of these complexes•In vitro study of antioxidant activity of ligands and their complexes