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Synthesis, characterization and crystal structure of N'-[(E)-furan-2-ylmethylidene]furan-2-carbohydrazide /
European Journal of Chemistry, Vol.5, Issue 3, pp.174-176, ISSN No: 2153-2249. -
Synthesis, characterization and photophysical studies of a novel schiff base bearing 1, 2, 4-Triazole scaffold
A novel Schiff base derivative containing 1, 2, 4-triazole nucleus (TMPIMP) was synthesized from 4- [1,2,4] triazol-1-ylmethyl-phenylamine and salicylaldehyde in the presence of glacial acetic acid in an ethanolic medium. The synthesized compound was characterized by 1H-NMR, IR and UV spectral analysis. The excitation and emission spectra of triazolyl methyl phenyl imino methyl phenol (abbreviated as TMPIMP) were recorded in various solvents to investigate their solvatochromic behaviour. Dipole moments of the two electronic states of TMPIMP were calculated from solvatochromic spectral shifts. These were correlated with refractive index (?) and dielectric constant (?) of various solvents. Theoretical calculations were performed to estimate the excited state dipole moment on the basis of different solvent correlation methods, like the Bilot-Kawski, Bakhshiev, Lippert-Mataga, Kawski-Chamma-Viallet and Reichardt methods. The dipole moment in the excited state was found to be higher than that in the ground state due to a substantial redistribution of electron densities and charges. Using a multiple regression analysis, the solvent-solute interactions were determined by means of Kamlet Taft parameters (?, ?, ??). Computational studies were performed by Gaussian 09 W software using a time-dependent density functional theory (TD-DFT) in order to calculate the atomic charges and frontier molecular orbital energies in the solvent phase. The calculations indicated that the dipole moment of the molecule in an excited state is much higher than that in a ground state. The chemical stability of TMPIMP was determined by means of chemical hardness (?) using HOMO-LUMO energies. The reactive centers in the molecule were also identified by molecular electrostatic potential (MESP) 3D plots as a result of TD-DFT computational analysis. 2016 Elsevier B.V. All rights reserved. -
Synthesis, characterizations, and electrochromic studies of WO3 coated CeO2 nanorod thin films for smart window applications
In this work, Cerium oxide nanorods were synthesized on Fluorine doped Tin oxide (FTO) substrate by a hydrothermal technique involving Ce(NO3)36H2O (Cerium Nitrate Hexahydrate) and CH4N2O (Urea). The DC magnetron sputtering was used to deposit a thin layer of WO3 on Cerium Oxide nanorods in the presence of argon gas at room temperature. With the prepared CeO2/WO3 thin films as the working electrode, saturated AgCl2 as the reference electrode, and platinum mesh as the counter electrode, a three-electrode electrochemical cell was developed with 0.5 M H2SO4 solution diluted in deionized (DI) water as the electrolyte. The electrochromic studies displayed a coloration efficiency of 10.14 cm2/C for 0.1 M film. SEM, UVVisible, XRD, and electrochemical analyzer were used to investigate the surface morphology, optical properties, composition, and electrochromic performance of the prepared thin films. A combination of CeO2 nanorods and WO3 coating has been proved to be a potential material for Electro Chromic Devices (ECD), because of its large charge capacity and optical transmission behavior. 2022 Elsevier B.V. -
Synthesis, Computational, and Photophysical Probing Studies on Mono-Azo Sulfonamides, and Their Antibacterial Activity
Abstract: Objective: Novel azo-linked substituted sulfonamides were synthesized via diazo coupling with the molecular formula (C9H10N4O2S2, C11H11N3O2S) and characterized by FT-IR, UV-vis, HR-MS, and 1H NMR spectroscopy techniques. The photophysical studies were carried out using experimental techniques. Absorption and fluorescence maxima of all the synthesized molecules were determined by using different solvents. Our synthesized mono-azo derivatives are interested in identifying the cellular target site for sulfonamides (F1-F2) and (P1-P2). The newly synthesized compounds were examined for their in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli strains. Methods: In this study, we focused on the sulfonamide architecture. Antibacterial activity of compound (F1), (F2), (P1), and (P2) derivatives was studied by measuring the diameter of the inhibition zone, using the Disc-agar diffusion method. Results and Discussion: Density functional theory was used to demonstrate the electronic and optical properties of the synthesized molecules. In the correlation between the HOMOLUMO energy gap, the derivative (F1) shows a higher (3.9866 eV) and (F2) shows a lower (3.2063 eV) excitation energy. The synthesized compound (F1) looks into antibacterial activity, exhibited more zone inhibition 25 mm in the concentration 75 L/mL in gram-negative bacteria when compared with the common antibiotic Ciprofloxacin. Additionally, the results emerged from the in silico molecular docking studies the compound (F2) showed highest binding energy against cyclin-dependent kinase (?Gb = 9.8 kcal/mol). Conclusions: The synthesized four mono-azo sulfonamide derivatives (F1), (F2), (P1), and (P2) are reported in photophysical, CDFT, antibacterial, and molecular docking studies with relevant results. Pleiades Publishing, Ltd. 2024. -
Synthesis, crystal structure and photophysical properties of (E)-4-(4-(2-hydroxybenzylideneamino)benzyl)oxazolidin-2-one
A new Schiff base, (4-(benzylideneamino)benzyl)oxazolidin-2-one has been synthesised from 4-(4-aminobenzyl)oxazolidin-2-one and salicylaldehyde by a simple condensation reaction. Single-crystal X-ray analysis of (E)-4-(4-(2-hydroxybenzylideneamino) benzyl)oxazolidin-2-one (HBOA) revealed that there is a 1-D, slipped, face-to-face motif with off-set, head-to-tail stacked columns. Detailed studies on photophysical properties of the synthesised compound in solutions indicate their potential applications in the field of organic light emitting devices and nonlinear optical materials. Absorption and fluorescence study of HBOA has been conducted in a series of solvents with increasing polarity at room temperature. Ground and excited state dipole moments have been determined experimentally by using LippertMataga polarity function, Bakhshiev solvent polarity parameter, KawskiiChammaViallet solvent polarity parameter and Richardt?s microscopic solvent polarity parameter. Due to the considerable ?-electron density redistribution, the excited state dipole moment was found to be larger than that of the ground state. The ground state dipole moment value was determined by quantum chemical method which was used to estimate excited state dipole moment through solvatochromic correlations. KamletTaft and Catalan methods were used to get the information of both non-specific solutesolvent interactions and hydrogen bonding interactions. TD-DFT (B3LYP/6-311G(d,p)) has been used for the determination of HOMOLUMO energies. Mulliken charges and Molecular electrostatic potential were also evaluated from DFT calculations. 2016 Elsevier B.V. -
Synthesis, DFT and In Silico Anti-COVID Evaluation of Novel Tetrazole Analogues
A new series of 3-aryl/heteroaryl-2-(1H-tetrazol-5-yl) acrylamides have been synthesized through catalyst-free, one-pot cascade reactions, utilizing click chemistry approach and evaluated for their anti-COVID activities against two proteins in silico. The structural properties of the synthesized molecules were evaluated based on DFT calculations. Total energy of the synthesized tetrazole compounds were obtained through computational analysis which indicate the high stability of the synthesized compounds. The Frontier Molecular Orbitals (FMO) and associated energies and molecular electrostatic potential (MEP) surfaces were generated for the compounds. Spectral analysis by DFT gave additional evidence to the structural properties of the synthesized molecules. All tetrazole analogues come under good ADMET data as they followed the standard value for ADMET parameters. Docking studies offered evidence of the molecules displaying excellent biological properties as an anti-Covid drug. Compound 4 g exhibited excellent anti-COVID-19 properties with four hydrogen binding interactions with amino acids GLN 2.486 GLN 2.436 THR 2.186 and HSD 2.468 with good full-fitness score (1189.12) and DeltaG (7.19). Similarly, compound 4d shown potent activity against anti-COVID-19 mutant protein (PDB: 3K7H) with three hydrogen binding interactions, i.e., SER 2.274 GLU 1.758 and GLU 1.853 with full-fitness score of 786.60) and DeltaG (6.85). The result of these studies revealed that the compounds have the potential to become lead molecules in the drug discovery process. 2022 Taylor & Francis Group, LLC. -
Synthesis, Green Photoluminescence and Studies of Nonlinear Optical Spatial Self Phase Modulation Effect in 2D Ga2Te3 Nanosheets
The liquid-phase exfoliation (LPE) technique has been employed to prepare two-dimensional (2D) gallium telluride (Ga2Te3) nanosheets with an average thickness of ?2.4 nm and linear optical properties, including UV-visible absorption and photoluminescence (PL) emission characteristics of the sample in the green wavelength region are reported. The third-order nonlinear optical (NLO) responses of the colloidal suspension of 2D Ga2Te3 are determined at 532 and 632 nm wavelengths by a spatial self-phase modulation (SSPM) experiment. The value of the third-order NLO refraction coefficient (n2e) and effective susceptibility for monolayer (?(3)Mono) 2D Ga2Te3 under 532 (632) nm continuous wave (CW) excitation is extracted to be 2.60 10-7 (0.32 10-7) cm2/W and 1.12 10-9 (1.37 10-10) e.s.u., respectively. The origin of the observed SSPM patterns under 532 nm excitation was elucidated theoretically. Finally, the correlation of ?(3)Mono with the mobility of charge carriers for a vast number of 2D materials is utilized to establish the origin of the observed NLO effect under 532 nm pump laser radiation in the 2D Ga2Te3. Additionally, NLO absorption coefficients of 2D Ga2Te3 have been extracted using the femtosecond Z-scan technique at 800 nm. We observed a switching behavior (saturable to threephoton absorption) in the nonlinear absorption mechanism with different input peak intensities. The highest three-photon absorption coefficient of ?1.68 cm3/GW2 was observed for a 350 GW/cm2 peak intensity. We believe that such reports of interesting linear and NLO properties of this newly synthesized 2D material can be utilized in the future for a wide number of optoelectronic applications. 2023 American Chemical Society. -
Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets
The physical vapour deposition (PVD) method has been employed to yield gallium telluride (GaTe) platelets. The morphology and growth mechanism of these platelets were investigated with the aid of scanning electron micrographs. The stoichiometry and homogeneity of the grown samples were confirmed by chemical analysis. The X-ray diffraction (XRD) technique has been used to explore the structure and phase of the compound. On the basis of the Archimedes principle, the density of crystals was estimated to be 5.442 kg mm-3. The resistivity and conductivity type were determined by the van der Pauw method. UV-vis-NIR studies revealed a direct transition with an energy gap of 1.69 eV. Mechanical properties such as microhardness, toughness, Young's modulus and elastic stiffness constant of GaTe crystals in response to the stress field due to an external load were studied to realize their suitability for radiation detector applications. The present observations provide an insight into the physical properties of the vapour-grown GaTe platelets, which are found to be superior over their melt counterparts. 2014 International Union of Crystallography. -
Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets /
Journal Of Applied CrystalloGraphy, Vol.47, Issue 6,pp.1841-1848, ISSN No: 1600-5767. -
Synthesis, in vitro and theoretical studies on newly synthesized deep blue emitting 4-(p-methylphenylsulfonyl-5-aryl/alkyl)oxazole analogues for biological and optoelectronic applications
In the present study, a series of 4,5-di-substituted oxazole derivatives (compounds 2a-p) were synthesized, using a novel methodology for the simultaneous determination of their biological and optoelectronic applications. Among the screened molecules, compounds 2j, 2 l and 2o showed very good antimicrobial potencies with MICs up to 1 g/mL. Furthermore, the photophysical parameters were estimated using theoretical and experimental techniques for optoelectronic applications. The excited-state dipole moment being higher than that of the ground state, investigated using solvato-chromatic method showed a redistribution of the electron densities in the excited state for the fluorophores. The HOMO-LUMO energies of the fluorophores estimated by using density functional theory (DFT) are found to be in good agreement with the experimental values. The electrophilic and nucleophilic sites were also recognized with the help of molecular electrostatic potential 3D plots using time-dependent-DFT computational analysis. The specific and non-specific interactions between the solutesolvent were analyzed by multiple linear regression analysis using Kamlet-Abound-Taft and Catalan parameters. Further, the global chemical reactivity descriptor parameter was also calculated. The photophysical properties of the fluorophores suggest that these may be considered as potential probes for OLED, solar cell, and chemosensor applications. 2022 Elsevier B.V. -
Synthesis, Mechanical Properties and Thermal Stability of Polydimethylsiloxane Nanocomposites
The polydimethylsiloxane/nano-graphite (PDMS-NG) nanocomposites were prepared via a two rolled mixing mill and subjected to characterization using techniques such as Transmission Electron Microscopy (TEM), stress-strain analysis during elongation, as well as thermal properties including Thermo-Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The transition temperature was observed to be below-70C for PDMS nanocomposites reinforced with Nano-Graphite (NG). The thermogram from the thermo-gravimetric analysis indicated that at 10%, 20%, 30%, and 50% weight loss, the temperatures for PDMS nanocomposites were higher compared to unfilled PDMS. These findings suggest a substantial improvement in the thermal stability of PDMS-NG nanocomposites. 2023, Books and Journals Private Ltd. All rights reserved. -
Synthesis, Photophysical, and Computational Studies of Mono-Azo-Bridged, Meso-Tris(2-Furyl/2-Thienyl) Substituted Porphyrin-Arene Hybrids
Porphyrins hybrids have been used as models to study various energy/electron transfer processes. The linkers connecting various subunits in such hybrids are vital in establishing good electronic communication between the subunits and the azo-bridge can be one of the efficient linkers to do so. Despite of these, the mono azo-bridged porphyrin-arene hybrids reported in the literature are only handful and the methods used to create them are not that efficient. In addition, the porphyrins used in this field so far contains only six-membered meso-substituents. By keeping these points in mind, we have developed a mild, one-pot, work-up-free, high-yielding method to synthesize mono-azo-bridged, porphyrin-arene hybrids which also features porphyrins containing three five-membered substituents like 2-furyl or 2-thienyl on their meso-positions. Along with the NMR and mass characterizations, the photophysical and computational studies of all the reported hybrids are presented. The hybrids containing meso-tris(2-furyl/thienyl) substituted porphyrins displayed red-shifted absorption and emission bands compared to their all-meso-aryl-containing counterparts. In general, all the hybrids displayed enhanced fluorescence quantum yields compared to their precursor porphyrins. Among the series, the meso-tris(2-furyl) substituted porphyrin-arene hybrids exhibited the more significant Stokes shift and small bandgap. The computational studies were in good agreement with the experimental findings. 2024 Wiley-VCH GmbH. -
Synthesis, Properties and Applications of Polymer Nanocomposites-A Review
Polymer nanocomposites have been a rapidly expanding research topic for producing materials over the last few decades. In the previous two decades, there has been a significant scientific interest in nanoscience and nanotechnology. Nanomaterials' distinct features are related to quantum phenomena, greater surface area, and self-assembly. Quantum effects can begin to dominate matter's behaviour in the nanoscale, particularly at the lower end, affecting optical, electrical, and magnetic properties. Nanomaterials have evolved into nanocomposites with numerous applications. Its applications catapulted them to prominence in the field of material research. Because of their unique property combinations and design practicality, polymer nanocomposites are employed in sports equipment, wastewater treatment, the automobile industry, and biomedical applications. Even though they have numerous advantages, producing them in sufficient quantities and high quality is still one of the biggest challenges. During the last few decades, polymer nanocomposites have been a fast-developing research topic for material production. There has been a surge in scientific interest in nanoscience and nanotechnology during the last two decades. Nanomaterials have developed into nanocomposites, which have a wide range of uses. Its uses propelled them to the forefront of material research. Nanocomposites physical, mechanical, barrier, flame retardancy, optical, dielectric, rheological, and thermal characteristics have been thoroughly researched. Their uses have also been discussed. 2024, Informatics Publishing Limited. All rights reserved. -
Synthesis, spectral and DNA/Protein binding evaluation of novel Cu(II) chelates of an NNO donor tridentate aroylhydrazone: Halogen bonding directed close packing
An NNO donor aroylhydrazone monohydrate, HFPBH2O (3-fluoropyridine-2-carbaldehyde benzoylhydrazone monohydrate) was synthesized from 3-fluoropyridine-2-carbaldehyde and benzhydrazide and physicochemically characterised. The coordination behaviour of the aroylhydrazone with the metal ion is investigated through various physicochemical techniques and it is concluded that it binds to the metal ion predominantly in the enolate resonance form, while few complexes exhibit keto form of the ligand. The structure of [Cu(FPB)(OAc)(H2O)]H2O (4a) established by single-crystal X-ray diffraction method unveiled that the metal ion has a distorted square-pyramidal geometry in this complex. The coordination sites of Cu(II) ion are occupied by azomethine N, pyridyl N and iminolate O from a monodeprotonated hydrazone moiety and the remaining two positions are occupied by two oxygen atoms, one each from acetate ion and the water molecule. Potential applications of the complexes were studied by subjecting them to DNA/protein (BSA) binding studies using electronic and fluorescence spectroscopy. The complexes were found to bind with DNA/protein (BSA) with binding constants in the order of 104 M?1 to 105 M?1. The intercalative mode of binding of the complexes with DNA was proved using spectral studies and molecular docking. Furthermore, the complex [Cu(FPB)(N3)(H2O)2] (5) was found to cleave the DNA from form I to form II during gel electrophoresis studies. 2020 Elsevier B.V. -
Synthesis, spectral characterization and antimicrobial studies of novel acyl hydrazones of pacetoxybenzaidehyde
Novel acyl hydrazones derived from p-acetoxybenzaldehyde and various acid hydrazides have been synthesized. Synthetic procedure is simple and convenient and affords good yield. Elemental analysis and spectral results of the products arc also reported. 2015 Scientific Publishers. All Rights Reserved. -
Synthesis, structural characterization, electrochemical and photocatalytic properties of vanadium complex anchored on reduced graphene oxide
In this work, vanadium complex anchored reduced graphene oxide (rGO-VO) was successfully synthesized by coordination interaction with phenyl azo salicylaldehyde (PAS) coupled trimethoxy silyl propanamine (TMSPA). The physicochemical and microscopic properties of rGO-VO were studied with different analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, Scanning electron microscopy (SEM), and Transmission electron microscopy (TEM) which confirmed the synthesis of rGO-VO. The electrochemical studies of rGO-VO in glassy carbon electrode demonstrated high current density because of the amazing electrochemical properties of rGO. The photocatalytic studies of anchored rGO-VO and VO(acac)2 toward MB dye indicated that anchored rGO-VO with visible light irradiated MB was degraded fast as compared to VO(acac)2. 2021 Taylor & Francis Group, LLC. -
Synthetic Applications of Prins Cyclization in Natural Product Syntheses
The natural products having tetrahydropyran unit with multiple chiral centers serve as magnificent building blocks for various active pharmaceutical ingredients (APIs). Prins cyclization is one of the wonderful strategies to construct tetrahydropyran unit stereoselectively in asymmetric synthesis. In this account, we discuss our research efforts toward the synthesis of various natural products from the past two decades (20052020) by using Prins cyclization as a key step. Further, the synthetic utility of this reaction was investigated and well demonstrated on various molecules successfully. 2022 The Chemical Society of Japan & Wiley-VCH GmbH. -
Synthetic polymer hydrogels as potential tissue phantoms in radiation therapy and dosimetry
The efficacy of synthetic polymers as hydrogel phantoms for radiation therapy and dosimetry has been investigated for photon and charged particle (electron, proton and alpha particle) interactions. Tissue equivalence has been studied in terms of photon mass energy-absorption coefficients, KERMA (kinetic energy released per unit mass), equivalent atomic number and energy absorption build-up factors, relative to human tissues (skin, soft tissue, cortical bone and skeletal muscle), in the energy range 0.015-15 MeV. For charged particle interactions, ratio of effective atomic number is examined for tissue-equivalence in the energy region of 10 keV-1 GeV. Well established theoretical formulations are used for computation of photon mass-energy absorption effective atomic number, electron density and KERMA. Five-parameter geometric progression (G-P) fitting approximation is used to compute the values of energy absorption build-up factors. Effective atomic number for charged particle interaction is determined using logarithmic interpolation method. Using the analytical methodology, it has been revealed that all the selected synthetic polymers have good tissue-equivalence relative to all tissue except cortical bone. In particular, polyglycolic acid (PGA) and poly-lactic-co-glycolic acid (PLGA) prove to be best substitute material for photon interactions. On the other hand, % difference between effective atomic number for charged particle relative to human tissues is found least for polyethylene glycol (PEG) demonstrating adequate tissue-equivalence. Therefore, the present study is expected to be useful to choose most appropriate phantom material for radiation therapy. 2020 IOP Publishing Ltd. -
Systematic investigations of graphene layers in sub-bituminous coal
Coal is the plentiful and widely and universally used fuel. However, its structural characteristic makes a perception that it is only worthwhile for generating energy via combustion. Herein we report a simple method to synthesize nanometre-sized graphene sheets with amorphous carbon addends on the edges from sub-bituminous coal. The X-ray analysis reveals the presence of crystalline carbon in the amorphous background. The average number of carbon atoms and aromatic layers was estimated as ?21 and 8. The interlayer spacing d 002 for the aromatic lamellae of samples leached using HF and acetic acid, are found to be 0.352 and 0.376 nm, respectively. The oxidation of coal structure resulted in nanometre sized graphene having lateral size of 4.19 nm and stacking height of 2.3 nm. The Raman spectrum analysis confirmed the formation of finite sized, less defective graphene nanolayers with leaching. The crystalline carbon within the coal matrix displaced with chemical leaching, resulting nano-meter sized graphene sheets. The results also established that with HF leaching, carbon in coal becomes more stacked and ordered compared to organic acid leached coal. 2014 Pleiades Publishing, Ltd.