The utility of carbon as the base material for carbon paste electrodes has been considered for many years. In this work, we were applied MWCNT as a modifier and Schiff base chitosan and 5-nitro isatin as ionophore along with carbon. Prepared CPE shows a Nernstian response of 29.567 mV per decade in a wide linear dynamic range of 1.0 × 10-5 to 1.0 ×10-1 M for Mg2+ ion. The optimization process had performed by Mixture design in design expert software. This present sensor has a short time of response of about 10 s. The applicable pH range was obtained 3.51-9.0 and Detection limit was calculated 1.4 ×10-5 M. Lastly, the prepared sensor was used in the indirect potentiometry (potentiometric titration) as an indicator or working electrode. The data obtained from the experiments showed that the electrode is usable in analytical applications. Manuscript profile

In this work, the synthesis, spectral characterization, DFT calculations, and catalytic activity of thenew Pt(II) complexes with the ligand derived from benzimidazole derivatives have been described.The new heterocyclic ligands were obtained from the reaction of o-amino-ketones with hydrazinehydrate in high yieldandPt(II) complexes prepared from the coordination of the new ligands toPt(II) cation. The new compounds have been characterized by spectral and microanalytical data.The DFT calculations at the B3LYP/6-311+G(d,p) level were also applied to gain further insightinto the geometry of Pt(II) complexes. The catalytic activity of Pt(II) complexes in Biginellireactionwas also examined as heterogeneous catalysts. The results showed that the 3,4-dihydropyrimidin-2(1H)-ones have been synthesized, in excellent yields, under solvent-free conditions, by reaction oftert-butyl acetoacetate, alcohol, arylaldehydes, and urea in the presence of Pt(II) complexes as anefficient and heterogeneous and catalyst. Manuscript profile

Acridine and imidazole were combined and synthesized 3,8-disubstituted-propyl-3H-imidazo[4,5-a]acridine-11-carbonitrile, as a new derivative. The interaction of this new compound with the topoisomerase enzyme was studied by molecular dynamics simulation. The 3,8-disubstituted-3H-imidazo[4,5-a]acridine-11-carbonitrile structure has been optimized by the density functional theory method. According to the results obtained from the molecular dynamics simulation, Arg364, Lys532, Asp533, Tyr537, Arg590, Cys630, Asn631, Gln633 and Adenine11 interact with the ligand by hydrophobic interactions and Arg488 and Adenine12 interact with the ligand by hydrogen bond interactions. Due to the fact that some of these residues, Arg488 and Arg590 are located in the enzyme active site, the new ligand appears to be inhibitory effect. Also, the calculation of the Harmonic Oscillator Model for Aromaticity (HOMA) index showed that the 5-membered ring of ligand and the 6-membered ring attached to the 5-membered ring had more reactivity with the enzyme. The contribution of charged residues in the binding free energy of the ligand is greater than the uncharged residues. Manuscript profile