Fluorophore tagged mixed ligand copper(II) complexes: synthesis, structural characterization, protein binding, DNA cleavage and anticancer activity

Two fluorophore tagged copper(II) complexes Cu(phen)(L)(ClO4)(2)] (1) and Cu(bpy)(L)(H2O)(ClO4)](ClO4) (2), (where L=2-amino-1H-benzode]isoquinoline-1,3-(2H)dione (L), phen=1,10-phenanthroline and bpy=2,2 `-bipyridine) have been synthesized and structurally characterized. Structures of the copper complexes 1 and 2 were confirmed by single-crystal X-ray structure determination. The coordination geometry around the copper center of complexes 1 and 2 is distorted octahedral. The plasmid DNA cleavage activity of the complexes has been investigated by agarose gel electrophoresis and the study reveals that both the complexes have high plasmid DNA photo-cleavage activity. The binding interaction ability of the metal complexes with bovine serum albumin (BSA) was investigated using fluorescence spectroscopy. The cytotoxicity of the complexes has been evaluated by MTT (3-4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide) assay against A549 (adenocarcinoma human alveolar basal epithelial cells) and MCF-7 (breast cancer cell line) cell lines in comparison with cis-platin. Complexes 1 and 2 have exhibited better cytotoxic activity than cis-platin against A549 and MCF-7 cell lines. The cellular uptake study and localization of the complexes within the cells have been investigated by fluorescence microscopy. The cell staining and flow cytometry experiments suggest that complexes induce an apoptotic mode of cell death

Structural elucidation and Hirshfeld surface analysis of a novel pyrazole derivative: 3-(Benzod1,3dioxol-5-yl)-1-(3-chlorophenyl)-5-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole

The title compound 3-(benzod1,3dioxol-5-yl)-1-(3-chlorophenyl)-5-(2,4-dichlorophenyl)-4,5-dihydro-1H-pyrazole was synthesized by the reaction of (E)-1-(benzod1,3dioxol-5-yl)-3-(2,4-dichlorophenyl)prop‑2-en-1-one and (3-chlorophenyl)hydrazine hydrochloride. The synthesized compound was characterized by 1H NMR, 13C NMR and mass spectral analysis and finally the structure was confirmed by single crystal X-ray diffraction studies. The compound crystallizes in the triclinic crystal system with the space group P−1. The pyrazole ring in the chiral racemate adopts an envelope conformation with the compound possessing a chiral center at C3 with R conformation. The molecular structure involves C—H⋯π and Cg⋯Cg interactions. Also, the crystal structure is stabilized by both inter and intra-molecular hydrogen bonds of the type C—H…Cl and C—H…N respectively which can account for the stability of the molecule. Further, Hirshfeld surface analysis employing 3D molecular surface contours and 2D fingerprint plots have been used to analyze intermolecular interactions present in the solid state of the crystal

Synthesis, crystal structure studies and hirshfeld surface analysis of 6-chloro-7-hydroxy-4-methyl-2H-chromen-2-one

The title compound 6-chloro-7-hydroxy-4-methyl-2H-chromen-2-one, a coumarin derivative was synthesized and characterized by using spectroscopic tools such as mass spectra, NMR (1H and 13C) and finally the structure was confirmed by the single crystal X-ray diffraction studies. The title compound (C10H7ClO3) crystallized in the monoclinic crystal system, with the space group P21/n. The cell parameters were confirmed by both powder and single crystal X-ray diffraction studies. The molecule is planar with all the substituents at the same plane of the coumarin moiety. The crystal and molecular structure of the title compound is stabilized by inter molecular OH⋯O and CH⋯O hydrogen bonds. The structure also exhibits CCl⋯Cg halogen bond interactions and π⋯π stacking interactions, which contributes to the crystal packing. Further, Hirshfeld surface analysis was carried out to understand the intermolecular interactions along with their graphical visualization through 2D fingerprint plots

Environmentally benign synthesis of substituted pyrazoles as potent antioxidant agents, characterization and docking studies

Oxidative stress is an important cause of neurogenerative diseases; treatment with a reliable antioxidant with no side effects is a potential tool to overcome with such diseases. The aim of this study is to explore new and effective antioxidants and their mechanism; in this context, the manuscript demonstrates the greener approach for the synthesis of series of novel thiophene-pyrazole hybrids,5(a-m) through 3 + 2] annulation of chalcones,3(a-g) and phenylhydrazine hydrochloride,4(a-b) in citrus extract medium in the presence of tetrabutylammonium bromide. The structures were confirmed by spectroscopic and crystallographic studies and further screened in vitro for their free radical scavenging activities. Preliminary assessment results show that, among the synthesized series, compounds5c,5d,5f,5i,5j,5l, and5mhave potent antioxidant activities. Docking studies reveal that the ligands5e,5f,5m, and5qbind to superoxide dismutase at the Cu-Zn domain and thereby increase its activity and reduce reactive oxygen species; therefore, these ligands might be better antioxidant molecules which could down and regulate the oxidation stress within the body

Synthesis, spectral and X-ray crystal structure of 3-(3-methoxyphenyl)-5-(3-methylthiophen-2-yl)-4,5-dihydro-1H-pyrazole-1-carboxamide: Hirshfeld surface, DFT calculations and thermo-optical studies

Novel pyrazole derivative, 3-(3-methoxyphenyl)-5-(3-methylthiophen-2-yl)-4,5-dihydro-1H-pyrazole-1-carboxamide was synthesized, characterized by NMR, mass spectra, FT-IR, UV–Visible, TG-DTG and finally the three dimensional structure was confirmed by single crystal X-ray diffraction studies. A dihedral angle of 78.51(13)° between the pyrazole and the thiophene rings confirms the twisted conformation between the rings. C—H•••O and N—H•••O hydrogen bond interactions are extended through 3D network to form R22(8) supramolecular motif. The compound was found to be thermally stable up to 190 °C. Further, the intermolecular interactions of the crystal structure were analysed by Hirshfeld surface analysis. The molecular geometries and electronic structures of the compound were optimized, calculated with ab-initio methods. The electrophilic and nucleophilic regions of the molecular surface were identified. The solvent effects on the structural parameters were studied using different solvents. Non-linear optical properties of the title compound were investigated

Synthesis, characterization and hydrogen bonding attributes of halogen bonded O-hydroxy Schiff bases: Crystal structure, Hirshfeld surface analysis and DFT studies

Halogen bond has been the focus of crystal engineering for many decades. The role of intra molecular halogen bonds on adjacent intramolecular hydrogen bonding attributes has hardly been investigated. The O-hydroxy Schiff bases offer a good platform to shed light on these bonding aspects. The halogen bonded O-hydroxy Schiff bases were synthesized by the reaction of aldehydes with primary amines. Compounds were then characterized using mass, FTIR and NMR spectroscopic methods. Finally, the three dimensional molecular structures of all the Schiff base compounds were confirmed through single crystal X-ray diffraction studies. The crystal structures exhibit both inter and intramolecular hydrogen bond interactions. The O-H center dot center dot center dot N intramolecular interactions form the six membered pseudo chelate rings. The structures are also stabilized by C-O center dot center dot center dot pi, N-O center dot center dot center dot pi and pi center dot center dot center dot pi interactions. These molecular interactions were then quantified using Hirshfeld surface analysis. Further, the density functional theory calculations were employed using B3LYP hybrid functional with 6-311G+(d, p) level basis set to optimize the structural coordinates. The chemically active regions of the Schiff base molecules were identified by the analysis of molecular electrostatic potential surface. (C) 2019 Elsevier B.V. All rights reserved

Inductively coupled modular battery system for electric vehicles

This study proposes two novel modularised battery systems capable of controlling the power of each module independently, and with inductive interface for convenient battery swapping. The proposed systems aid in overcoming the limitations such as unavailability of <i>electric vehicle</i> (EV) due to battery pack fault and lengthy battery recharging time which largely hampers the adoption of EVs for personal transportation. The proposed systems consist of a plurality of battery modules which are wirelessly coupled to the EV through inductive power transfer technology. The proposed systems are described in detail, and models are presented to analyse their steady-state behaviours. A design guideline for a 24 kWh 80 kW battery micro-pack system is discussed. Performances of the proposed topologies are investigated using simulations. To demonstrate the applicability, prototype systems of 1.5 kW are implemented and tested under various operating conditions. Results convincingly indicate that the proposed systems improve the vehicle's availability under fault condition

Thermal, optical, etching, structural studies and theoretical calculations of 1-(2, 5-Dichloro-benzenesulfonyl)-piperidin-4-yl]-(2,4-difluoro-phenyl)-methan one oxime

The title compound 1-(2,5-Dichloro-benzenesulfonyl)-piperidin-4-yl]-(2,4-difluoro-phenyl )-methanoneoxime was synthesized by the substitution reaction of 2,4-difluorophenyl(piperidin-4-yl)methanone oxime with 2,5-Dichloro-benzenesulfonylchloride. The synthesized compounds were characterized by different spectroscopic techniques. The structure of the compound was confirmed by single crystal X-ray diffraction studies, which revealed that the piperidine ring adopts a chair conformation. The geometry around the S atom is distorted tetrahedral. The structure exhibits both inter and intra molecular hydrogen bonds of the type O-H center dot center dot center dot O and C-H center dot center dot center dot O. The crystal structure is also stabilized by C-Cl center dot center dot center dot pi and pi center dot center dot center dot pi interactions. Further, the intermolecular interactions are quantified by Hirshfeld surface analysis. The three dimensional energy framework analysis was carried out and the interaction energies between the molecules were computed. The density functional theory calculation was employed to optimize the structural coordinates and the results substantiate the experimental findings. The HOMO-LUMO energy gap and other electronic parameters of the molecule were evaluated. Further, the reactive sites on the molecular surface were identified using molecular electrostatic potential map. Finally, the thermal properties of the crystals were studied using thermogravimetric analysis which revealed that the structure was stable in the temperature range of 20-170 degrees C. (C) 2020 Elsevier B.V. All rights reserved