Nurettin Menges

Unsymmetrical pyrazole-based new semiconductor oligomer: synthesis and optical properties

Poly(p-phenylene-1-(2,5-dimethylphenyl)-5-phenyl-1H-pyrazole-3,4-dicarboxy amide) (poly(PDPPD)) was synthesized from reactions of p-phenylene-diamine and 1-(2,5-dimethylphenyl)-5-phenyl-1H-pyrazole-3,4-dicarbonyl dichloride (monomer) by heating under solvent. This newly synthesized poly(PDPPD) was characterized by 1H, 13C-NMR, FT-IR, gel permeation chromatography (GPC). In addition, we investigated optical properties of the poly(PDPPD) containing the substituted pyrazole ring at different molarities. The average transmittance (Tavg) values of the poly(PDPPD) in the visible (V) region were higher than the Tavg values in the near-ultraviolet (NU) region. The Tavg values of the poly(PDPPD) in the NU and visible (V) region decreased with increasing molarity. The absorption band edge (Absbe) value of the poly(PDPPD) decreased with increasing molarity. It was observed that the optical band gap (Eg) of the poly(PDPPD) value decreased more with increasing molarity. The refractive index of the poly(PDPPD) decreased with increasing wavelength and decreasing molarity. The structure of the poly(PDPPD) in the lowest energy was optimized by DFT calculation and its HOMO–LUMO orbitals were plotted.

Indole-containing new types of dyes and their UV-vis and NMR spectra and electronic structures: Experimental and theoretical study.

Indole containing dyes were synthesized via a simple method with high yield. These molecules have different colors and UV-vis spectra of them were recorded. Impact of solvents on absorbances was investigated and it was observed that basic solvent such as DMF and pyridine have blue shift. TD-DFT calculations were done and results were compared with experimental data. NMR data of molecules were analyzed and tautomeric forms of colorants and their ratio were determined. It was find out that two tautomers might be formed in solution, called indole and indolenine form. HOMO-LUMO and energy gaps were calculated and plotted. Furthermore, molecular electrostatic potentials were simulated to find out electrophilic and nucleophilic regions.

Synthesis of novel imidazopyridines and their biological evaluation as potent anticancer agents: A promising candidate for glioblastoma

Novel imidazopyridine derivatives were synthesized according to a very simple protocol and then subjected to cytotoxicity testing against LN-405 cells. Two of the compounds exhibited antiproliferative effects on LN-405 cells at 10 and 75 µM and were selected as lead compounds for further study. Safety experiment for lead compounds on WS1 was carried out and IC50 values were calculated as 480 and 844 µM. LN-405 cell line were incubated with the lead compounds and then tested for DNA damage by comet assay and effects on cell cycle using flow cytometry. The results of these two tests showed that both lead compounds affected the G0/G1 phase and did not allow the cells to reach the synthesis phase. The log BB (blood-brain barrier) and Caco-2 permeability of the synthesized molecules were calculated and it was shown that imidazopyridine derivatives taken orally are likely to pass through gastrointestinal membrane and the blood-brain barrier.

Synthesis and evaluation of aromaticity and tautomerization of pyrazolopyridazin(on)es

Aromaticity of pyrazolopyridazin(on)es was investigated using NICS(0), NICS(1), NICSzz(1), FIPC-NICS and HOMA aromaticity indexes and it was observed that aromaticity of pyridazin(on)es was amenable to aromaticity of pyrazole and vice versa. Some tautomeric forms of pyridazinone were analyzed and the localized orbital locator maps, electron density maps, Fuzzy, Laplacian, and Mayer bond order methods showed dominant form. Different substituents, amine, chlorine, phenyl, methyl, hydrogen, substituted-phenyl, etc. on both the rings were chosen to search out the substituent effect. Aromaticity of pyrazolopyridazin(on)es was searched out in detail for the first time.Graphical AbstractSynopsis: Aromaticity of Pyrazolopyridazine was calculated and the effect of bicyclic system on aromaticity was revealed. Furthermore, tautomerization of the same skeleton was investigated and the dominant tautomer was identified by means of aromaticity, bond order, and LOL map.