Publications

Coumarins play an important role in drug development with diverse biological applications. Herein, we present the synthesis of coumarin through Pechmann reaction by using zirconia-based heterogeneous catalysts (ZrO2-TiO2, ZrO2-ZnO, and ZrO2/cellulose) in a solvent-free condition at room temperature. ZrO2-TiO2, ZrO2-ZnO, and ZrO2/cellulose were identified through spectroscopic techniques such as FESEM, X-ray, EDS, XPS, and FT-IR. ZrO2-TiO2 showed the best catalytic performance while ZrO2/cellulose was inactive. The kinetic parameters were observed in a solvent-free condition as well as in toluene and ethanol. The temperature effect was extensively studied which revealed that increasing the temperature will increase the rate of reaction. The rate of reaction in a solvent-free condition, ethanol, and toluene were 1.7 × 10(-3), 1.7 × 10(-2), and 5.6 × 10(-3) g mol(-1) min(-1), respectively.

The thia-zole-pyridazine fused-ring system of the title compound, C(13)H(12)N(4)O(3)S(2), is approximately planar (r.m.s. deviation = 0.037 Å); the benzene ring connected to the fused-ring system through the N atom is twisted by 39.3 (1)°. The amine group uses an H atom to form a hydrogen bond to the ketonic O atom of an inversion-related mol-ecule to generate a dimer; adjacent dimers are linked by an N-H⋯O hydrogen bond to form a linear chain.

Abstract In an alkaline solution, mercuric oxide decorated carbon nanotube nanocomposites (HgO.CNT NCs) were manufactured utilizing an uncomplicated wet‐chemical approach. Ultra‐Violet spectroscopy (UV‐Visible), Fourier Transform Infra‐red spectroscopy (FTIR), Powder X‐ray Diffraction (XRD), X‐ray Photo‐electron Spectroscopy (XPS), and Field Emission Scanning Emission Microscopy (FESEM), X‐ray Electron Dispersive Spectroscopy (XEDS) techniques were applied to examine the HgO.CNT NCs that had been prepared. Ascorbic acid sensor was developed upon light coating of HgO.CNT NCs on polished Glassy carbon electrode (GCE) modified with nafion (Nf). Analytical performance of the selected ascorbic acid sensor was achieved such as sensitivity, Limit of quantification (LOQ), Limit of detection (LOD), Linear dynamic range (LDR), extended reliability, interference effect experimentation, and actual sample inspection using a consistent current‐voltage approach. Calibration curve of the suggested sensor was observed to be linear ( R 2 =0.9957) throughout a broad range of ascorbic acid concentrations (100.0 pM∼100.0 mM) at a voltage of 0.8 V. The calibration curve yielded analytical parameters such as sensitivity (632.91 pAμM −1 cm −2 ), LOQ (255.0 pM), LOD (76.50 pM), and LDR (100.0 pM ∼1.0 mM) for the proposed ascorbic acid sensor (GCE/HgO.CNT NCs/Nf). The wet‐chemical synthesis of HgO.CNT NCs is a good development of nanocomposite‐oriented sensor advancement in medical sciences with non‐enzymatic detection of biological substances. This proposed sensor applied to selective ascorbic acid detection in biological samples and obtained logical outcomes.

In the title compound, C(22)H(14)BrN(3), the fused-ring system is buckled owing to the ethyl-ene linkage in the central ring; the two flanking aromatic rings are twisted by 25.9 (1) ° with respect to each other. The phenyl ring is twisted by 77.0 (1)° relative to the amino- and cyano-bearing aromatic ring. In the crystal, adjacent mol-ecules are linked by two N-H⋯N hydrogen bonds, generating a zigzag chain along [101].

A pyridine-pyrazoline (2-(3-(pyridin-2-yl)-5-(3,4,5-trimethoxyphenyl)-4,5-dihydro-1H-pyrazol-1-yl)benzo[d]thiazole) (PTPB) has been designed and synthesized by the reaction of chalcone with 2-hydrazinylbenzo[d]thiazole. PTPB was further conformed by the FT-IR, 1H-NMR and 13 F. Ran, Y. Liu, D. Zhang, M. Liu, and G. Zhao, “Discovery of Novel Pyrazole Derivatives as Potential Anticancer Agents in MCL,” Bioorganic and Medicinal Chemistry Letters 29, no. 9 (2019): 1060–4.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]N-NMR spectroscopic techniques. The solvatochromic behavior of PTPB with electron donating and accepting group was investigated in nonpolar, polar aprotic and protic solvents experimentally. The photophysical behavior of the PTPB in different solvent was attributed to the intramolecular charge transfer (ICT) of the compound along with specific and nonspecific interaction with different solvents. On view of the effect of different type of interaction on the photophysical parameters such as stokes shift, dipole moment oscillator strength and fluorescence quantum yields have been calculated with respect to polarity of the solvent. In addition, pyridine-pyrazoline (PTPB) can use as fluorescent chemosensor to determine the Fe3+ metal ion with high selectivity among the series of cations in aqueous dimethylformamide (DMF). The recognition mechanism of PTPB toward Fe3+ has been investigated in detail by Benesi–Hildebrand, Stern–Volmer and job’s plot measurements and PTBP forms 1:1 complex with Fe3+ metal ion and displays fluorescent quenching behavior.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Advanced poly(O-Toluidine) Sn(II) silicotungstate (POTSn(II)SiO2WO3) ternary nanocomposite synthesized by the extremely well-known simple sol–gel method. We have selected a low-cost o-toluidine monomer initiator and abundantly available metal of divalent tin with the silicon tungstate moieties that may work as the exchange sites for the metal ions. The poly(O-toluidine) Sn(II) silicotungstate was prepared by the oxidative polymerization of o-toluidine by potassium persulphate in situ mixings of the Sn(II) tungstate prepared in the separate conical flask at 5 pH. The obtained composite was characterized by various spectrophotometric techniques viz, SEM-EDX, XRD, TGA, FTIR, and its physicochemical characterization was carried out by determining its potential as an ion-selective membrane electrode. The ion-selective membrane was prepared and characterized for, porosity, swelling, and thickness. Based on high porosity and low thickness, the membrane was selected for further studies for the preparation of the selective membrane electrode and found selective for Cd2+. Based on the calibration curve, the Nernstian response was found near the Nernstian response (29.74), good pH range, and broad selectivity range of the metal ion. This ion-selective membrane electrode would be utilized for the determination of metal in unknown samples.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.