Synthesis, characterization, and in vitro effect of the Cu(II) complex with niflumic acid and 3‐picoline on paraoxanase‐I

Abstract

Niflumic acid is used to treat inflammatory rheumatoid diseases, pain, and fever. The present study reports the experimental, spectroscopic, thermal, structural analyses, and biological activities of this complex. The nonsteroidal anti-inflammatory drug niflumic acid, 3-picoline, and copper(II) chloride were utilized to synthesize a new complex: [Cu 2 Cl 2 (nif) 2 (3-pic) 4 ]. The crystal structure of [Cu 2 Cl 2 (nif) 2 (3-pic) 4 ] was determined by X-ray crystallography. The complex crystallizes in the triclinic space group P-1 and each Cu(II) center displayed six-coordinated distorted octahedral geometry. Two Cu(II) centers are connected by a chloro-bridge to form the binuclear metal core. Finally, the in vitro effects of the synthesized new complex and free niflumic acid were evaluated on the human serum paraoxonase 1 enzyme. At low doses, both the new complex and free niflumic acid showed very good inhibition activity with different inhibition mechanisms. In addition, the results showed that the new complex has more inhibition activity than free niflumic acid.

Synthesis and characterization of four novel palladium(II) and platinum(II) complexes with 1‐(2‐aminoethyl)pyrrolidine, diclofenac and mefenamic acid: In vitro effect of these complexes on human serum paraoxanase1 activity

“…We have found that these complexes inhibit the PON1 enzyme. K i values (0.057–0.212 mM) obtained in present study were more effective than K i values (0.116–0.434 mM) in our previous studies . Furthermore, Alim and Beydemir investigated in vitro interactions between the PON1 enzyme and some sulfonamides.…”

“…Complex 3 and 4 showed less inhibition activity than 1 and 2 complexes, with K i of 0.155 and 0.212 mM, respectively. Complex 1–4 showed more inhibitory effect compared with recently reported PON1 inhibitors in the literature . Effects of different copper(II) complexes, which are derived dicarboxylic acid and naproxen, for PON1 enzyme have been researched until now by our group.…”

“…Then, it was purified by using DEAE‐Sephadex A‐50 anion exchange chromatography and Sephadex G‐200 gel filtration chromatography techniques, respectively. Purification methods of PON1 were carried out as previously described …”

“…Protein contents were determined spectrophotometrically at 595 nm during the purification steps according to the Bradford method by using bovine serum albumin as the standard, as previously reported …”

The paraoxonase 1 activity and lipid levels in umbilical cord blood and maternal venous blood, and their relations according to birth weight

“…The whole PON1 activity procedure was performed according to our previous studies [10,17]. Briefly, Paraoxonase activity of PON1 has been investigated with paraoxone (1 mM) in 50 mM glycine-NaOH (pH 10.5) buffer including 1 mM CaCl2 at 25°C.…”