Synthesis, structural, spectral and biological evaluation of metals endowed 1,2,4-triazole

Biologically active triazole Schiff base ligand 2,4-dichloro-6-[(1H-1,2,4-triazol-3-ylimino)methyl]phenol (A) has been synthesized by the condensation reaction of an equimolar amount of 1H-1,2,4-triazole-3-amine and 3,5-dichlorosalicylaldehyde and then it coordinated with salts of metals [VO(IV), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] in 2:1 molar ratio to derive a series of transition metal chelates (1)-(6). All the compounds were characterized by various physical, spectral, analytical techniques and elemental analysis. Spectral characterization and magnetic moment data of complexes revealed square pyramidal geometry for vanadium complex and octahedral for remaining (2)-(6) complexes. Quantum chemical calculation has been carried out to explore optimized geometry and electronic structure of the ligand. Density functional theory (DFT) with B3LYP/6-311+g(d,p) method was performed to determine vibrational bands, frontier molecular orbitals (FMOs) and natural bond analysis (NBO) of the ligand. NBO analysis showed that the ligand bears higher molecular stability because of hyper conjugate interactions. Computational study results revealed that there was a close interaction of theoretical and experimental spectroscopic data. Global reactivity descriptors calculated by the energies of FMOs, indicated ligand to be bioactive. The synthesized compounds were studied for antibacterial, antifungal, antioxidant and antiglycation activity and the results revealed that ligand has remarkable activity which considerably increased upon chelation.                     KEY WORDS: Triazole ligand, Transition metal chelates, Antibacterial, Antifungal, Antioxidant, Computational study   Bull. Chem. Soc. Ethiop. 2020, 34(2), 335-351 DOI: https://dx.doi.org/10.4314/bcse.v34i2.1

Excited state dependent fast switching NLO behavior investigation of sp2 hybridized donor crystal as D-π-A push–pull switches

This research focused on the investigating electronic and optical properties of designed chromophores (TPTP1-TPTP5) to involve their comprehensive analysis, including geometry optimization, UV–Vis spectroscopy, analysis of the transition density matrix (TDM), and exploration of their nonlinear optical (NLO) responses. The chromophore TPTP1 and TPTP2 exhibit significant transitions, making them suitable for optical switching applications. The chromophore TPTP5 stood out with high values for linear polarizability (, 8.53 × 10-24 esu), first order polarizability β0 (3.86 × 10-24 esu), and second order hyperpolarizability (γ0, 6.41 × 10-24 esu), making it notable for its nonlinear optical response. A positive correlation was observed between their vertical ionization potential (VIP) and the γ0 related NLO response, indicating that higher VIP values correspond to stronger γ0 responses. Their UV–Vis spectroscopy was employed to examine the absorption properties of the chromophores, revealing the wavelengths (λmax) at which they absorbed light and their potential for light harvesting applications. The analysis of the TDM allowed for a deeper understanding of the redistribution of electron density during electronic transitions within the chromophores. This analysis provided valuable insights into the characteristics and nature of their excited states. Additionally, the research investigated the NLO responses of the chromophores, particularly focusing on their third harmonic generation (THG) properties. These NLO properties are crucial for potential applications in optical switches, frequency conversion, and optical signal processing. Overall, the findings from this research contribute to a comprehensive understanding of the electronic and optical properties of the designed chromophores. The obtained results open up new possibilities for their utilization in various technological fields, including light harvesting, photonics, and nonlinear optics

Recent developments in chemistry, coordination, structure and biological aspects of 1-(acyl/aroyl)-3-(substituted) thioureas

1-(Acyl/aroyl)-3-(substituted)thioureas are privileged architectures that have received remarkable attention of researchers in view of their variable topological aspects, binding modes and broad spectrum promising pharmacological properties. Reactivity of acyl thiourea derivatives has presented various organic transformations into other demanding scaffolds and this is an attractive strategy for synthetic chemists to access heterocyclic cores. Multiple binding sites make them flexible ligands for complexation with transition metals thus occupying a distinct position in coordination chemistry. 1-(Acyl/aroyl)-3-(substituted)thioureas have also emerged as attractive candidates in various fields such as ion sensors, corrosion inhibitors, molecular electronics, in metal extraction and in pharmaceuticals. The medicinal chemistry of this organo-sulfur framework and the derived metal complexes has witnessed fantastic progress in the current era. In continuation of our efforts to compile data on the structural aspects and numerous applications of 1-(acyl/aroyl)-3-(substituted)thiourea analogs, continuous advances have prompted us to present an overview of the last 2 years literature on this exciting family of compounds through this review article.Fil: Saeed, Aamer. Quaid-i-Azam University; PakistánFil: Qamar, Rabia. Quaid-i-Azam University; PakistánFil: Fattah, Tanzeela Abdul. Quaid-i-Azam University; PakistánFil: Flörke, Ulrich. Universität Paderborn; AlemaniaFil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentin