Search

The structural and biological mechanism of a drug material was investigated by spectroscopic techniques and molecular modeling methods. The experimental spectroscopic techniques, namely Fourier Transform Infrared and Fourier Transform Raman spectroscopies are recorded for the structural confirmation and were also compared with computed values. The stability of the compound, the intermolecular and intra molecular interactions is studied using the density functional theory tool Gaussian 16 W. The optimized molecular geometry, vibrational wavenumbers, infrared intensities, and Raman scattering activities are calculated. Natural Bond Orbital analysis has been carried out to explain the charge transfer (or) delocalization of charge due to the intra molecular interactions. The Time dependent-Density functional theory is used to evaluate the excitations between different energy levels, the interpretation which affords good information about D-(-)-alpha-Phenylglycine's electronic properties with different solvation effects. Reactive sites were also analyzed using topological studies. To explore the biological activities docking studies of D-(-)-alpha-Phenylglycine is performed with Prolactinoma and hyperprolactinemia diseases. [ABSTRACT FROM AUTHOR]

In the present study, the chlorophenyl substituted chalcone derivative molecule ((2 E)-3-(biphenyl-4-yl)-1-(4-chlorophenyl) prop-2-en-1-one (BCPO)) was synthesized and characterized by spectroscopic (FT-IR, FT-Raman and UV-Vis) techniques. In addition, the molecular structures of chlorophenyl, hydroxyphenyl, nitrophenyl substituted chalcone derivative ((2 E)-3-(biphenyl-4-yl)-1-(4-chlorophenyl) prop-2-en-1-one (BCPO), (2 E)-3-(biphenyl-4-yl)-1-(4- hydroxyphenyl) prop-2-en-1-one (BHPO) and (2 E)-3-(biphenyl-4-yl)-1-(4-nitrophenyl) prop-2-en-1-one (BNPO)) molecules were optimized. The vibration frequencies were calculated and compared with experimental spectral data of BCPO molecule. The molecular orbital occupancies were computed using highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) analyses, and time-dependent density functional theory (TDDFT) applied to calculate Ultraviolet (UV) - Visible absorbance spectra using a solvated approach. The molecular reactivity chemical behaviour of the BCPO, BHPO and BNPO compounds with their electrostatic potential charge identifications, electrophilic, and nucleophilic individual atomic reactions were performed using molecular electrostatic potential (MEP) maps, Fukui functions, and dual descriptors studies. Non-linear optical properties, intermolecular energy transfer, bonding types, and stabilization energies were performed by natural bond orbital (NBO) analysis. The molecular stabilization and intermolecular interactions of BCPO molecule were performed using Hirshfield and 2D finger plot analysis. The antimalarial activities of BCPO, BHPO and BNPO molecules were obtained using molecular docking analysis. [ABSTRACT FROM AUTHOR]

The title compound, (E)-1-(5-bromo-2-hydroxybenzylidene)semicarbazide (15BHS) was synthesized and characterized by FT-IR, FT-Raman, UV, 1 HNMR and 13 CNMR spectral analysis. The optimized molecular geometry, the vibrational wavenumbers, the infrared intensities and the Raman scattering activities were calculated by using density functional theory(DFT) B3LYP method with 6–311++G(d,p) basis set. The detailed interpretation of the vibrational spectra has been carried out by VEDA program. The calculated HOMO and LUMO energies show that charge transfer within the molecule. Stability of the molecule arising from hyperconjugative interactions, charge delocalization have been analyzed using natural bond orbital analysis (NBO). The first order hyperpolarizability, Molecular electrostatic potential (MEP) and Fukui functions were also performed. To study the biological activity of the investigation molecule, molecular docking was done to identify the hydrogen bond lengths and binding energy with different antifungal proteins. The thermodynamic properties (heat capacity, entropy, and enthalpy) of the 15BHS at different temperatures have been calculated. [ABSTRACT FROM AUTHOR]

The title compound, (E)-1-(3-bromobenzylidene)semicarbazide (3BSC) was synthesized and characterized by FT-IR, FT-Raman, UV, 1 HNMR and 13 CNMR spectral analysis. The optimized molecular geometry, the vibrational wavenumbers, the infrared intensities and the Raman scattering activities were calculated by using density functional theory (DFT) B3LYP method with 6–311++G(d,p) basis set. The calculated HOMO and LUMO energies show that charge transfer within the molecule. Stability of the molecule arising from hyperconjugative interactions, charge delocalization have been analyzed using natural bond orbital analysis (NBO). The hyperpolarizability calculation reveals the present material has a reasonably good propensity for nonlinear optical activity. Molecular electrostatic potential (MEP) and Fukui functions were also performed. The thermodynamic properties (heat capacity, entropy, and enthalpy) of the 3BSC at different temperatures have been calculated. The biological applications of 3BSC have been screened for its antimicrobial activity and found to exhibit antifungal and antibacterial effects. In addition, the Molecular docking was also performed for the different receptors. [ABSTRACT FROM AUTHOR]

The compound (E)-1-(4-bromobenzylidene)semicarbazide(4BSC) was synthesized and characterized by FT-IR, FT-Raman, UV–Visible, 1 HNMR and 13 CNMR spectra. The optimized molecular geometry(bond length, bond angle), the complete vibrational frequency, the infrared intensities and the Raman scattering activities were calculated by using density functional theory(DFT) B3LYP method with the help of 6–311++G(d,p) basis set. From the recorded UV–Visible spectrum, the electronic properties such as excitation energies, wavelength, band gap and oscillator strength are evaluated by TD-DFT in DMSO solution and gas phase methods using 6-311++G(d,p) basis set. The calculated HOMO - LUMO band gap energies confirm that charge transfer occurs within the molecule. The 1 H and 13 C nuclear magnetic resonance (NMR) chemical shifts of the molecule are calculated by the gauge-independent atomic orbital (GIAO) method and compared with experimental results. The hyperconjugative interaction energy E(2) and electron densities of donor (i) and acceptor (j) bonds were calculated using NBO analysis. Besides NLO and MEP were also calculated and interpreted. To study the biological activity of the investigation molecule, molecular docking was done to identify the hydrogen bond lengths and binding energy with different antimicrobial protein. Thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations the heat capacity (C), entropy (S) and enthalpy changes (H) and temperatures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Geometric structure was optimized and the band gap energies were calculated in monomer and dimer form. • Wavefunctional studies RDG, ELF were carried out. • Solvation effect model was implemented for HOMO-LUMO, and MEP studies. • Charge transfer due to excitation was explored. • Molecular docking studies proven biological activity of monomer and dimer and bindings sites were predicted. In the present study, structural, wavefunctional, electronic and charge transfer properties of 8-Quinolinesulfonamide are investigated by making the use of DFT tools Gaussian 16 W, and Gauss View 6. The optimized geometrical parameters, wavefunctional properties like reduced density gradient, chemical bonding and electron localization function are reported in monomer and dimer form. The calculated energies of HOMO and LUMO have been found to represent the electron excitation properties. Electrophilic and nucleophilic sites are found by MEP analysis. Spectroscopic wavenumbers (IR, Raman) are investigated computationally and UV–Visible spectrum was analyzed using TD-DFT method with solutions. To explain the charge transfer and stabilization energy due to inter or intra molecular interactions, the natural bond orbital analysis is performed. Furthermore, drug-likeness, ADME, molinspiration, environmental toxicity properties and the molecular docking study with monomer and dimer structure was also performed. [ABSTRACT FROM AUTHOR]

The title compound (RS) - 2- (1, 8-Diethyl- 4, 9-dihydro-3H- pyrano [3, 4-b] indol-1-yl) acetic acid (Etodolac) was characterized by experimental FTIR, FT-Raman, NMR and UV-Visible spectral analysis. The optimized molecular geometry and vibrational wave numbers were calculated by employing the method of DFT and B3LYP/6-311++G(d, p) basis set. The vibrational assignments were calculated using VEDA program. Carbon and Proton NMR chemical shifts were calculated in different solvents by GIAO method. Theoretical UV-Visible spectrum was obtained in DMSO and in gas phase using TD-DFT method. For the title compound, HOMO-LUMO and Donor- Acceptor (NBO) interactions were studied. In addition, MEP map was traced to find the reactive sites of Etodolac. Further, NLO properties such as dipole moment, linear and first order hyperpolarizabilities have been studied to reveal NLO nature of the title compound. Also the thermodynamic properties with respect to temperature were calculated. All the theoretical predictions were carried out by using DFT-B3LYP method at the level of 6–311++G(d, p). Finally to find its biological importance, the molecular docking interaction was studied to reveal that Etodolac is a selective inhibitor of COX (cyclooxygenase) enzyme. Image 1 • A detailed spectroscopic study (FTIR, FT-Raman, NMR and UV-Visible) on Etodolac was reported. • Optimized geometrical parameters were calculated by DFT-B3LYP/6-311++G(d,p). • Vibrational assignments on PED basis was carried out using VEDA program. • NBO, HOMO-LUMO, MEP, NLO and Thermodynamic properties were studied. • Molecular docking simulations have been performed using Auto Dock 4.2.6. [ABSTRACT FROM AUTHOR]

Abstract The molecule (RS)-2-(tert-Butylamino)-1-(3-chlorophenyl)propan-1-one (2B3CP) was optimized utilizing density functional theory (DFT) with B3LYP/6–311++G (d,p) basis set. The vibrational frequencies and potential energy distribution (PED) of 2B3CP molecules were calculated and compared with experimental calculations. The reactivity nature of the molecule was analyzed with various DFT methods such as local reactivity descriptors, Molecular electrostatic potential (MEP), Frontier Molecular orbitals (FMOs), Natural bond orbitals (NBO), etc. The molecular docking analysis reveals that inhibitory nature of the 2B3CP molecule with Adrenaline uptake inhibitor (PDB ID: 2AN5) protein act as neurotransmitter for Central nervous system (CNS) drug discovery. Hence, the present studies report the structural and bioactive nature of the title molecule. Graphical abstract Image Highlights • Molecular docking studies suggest that the compound exhibit adrenaline uptake inhibitor. • Spectroscopic analysis was done by experimental and DFT methods. • The complete assignments of FT-IR and FT-Raman modes were proposed based on the calculated PED % values. • NBO analysis was carried out and thermodynamic properties were predicted. • Hyperpolarizability, HOMO, LUMO energies and Fukui functions were calculated. [ABSTRACT FROM AUTHOR]

FT-IR and FT-Raman spectra of 5,5-diphenylimidazolidine-2,4-dione (55D24D) were recorded and theoretical study has been done by quantum mechanical calculations of DFT using Gaussian software package. The structural, vibrational and electronic properties of the title compound were presented using the B3LYP method with 6–311++G(d,p) basis set. The experimental vibrational spectra were compared with the calculated spectra and each wavenumber was assigned on the basis of potential energy distribution (PED). Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed utilizing Natural bond orbital (NBO) analysis. The electron density-based local reactivity descriptors such as Fukui functions are calculated to explain the chemical selectivity or reactivity site in the title compound. The linear polarizability ( α ) and the first order hyperpolarizability (β) values of the investigated molecule have been calculated. The HOMO and LUMO energies show the chemical activity of the molecule. Mulliken population analysis on atomic charges, Molecular electrostatic potential maps (MEP) and thermodynamical properties of title compound have been calculated. To study the biological activity of the investigation title molecule, molecular docking was done to identify the hydrogen bond lengths and binding energy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cefadroxil sulfoxide (CDSO) was synthesized and characterized by FT-IR, FT-Raman and UV–Visible spectroscopic technique. • Chemical reactivity and electronic properties were evaluated for the different solvents. • Electronic states DOS, TDOS and COOP analyses were estimated. • Topology analyses viz., ELF, LOL, RDG and electron hole were evaluated. • Molecular docking study and ADME properties were investigated for the anti-microbial targets. The cefadroxil sulfoxide (CDSO) para -hydroxy derivative, derived from cefadroxil, has enormous significance in pharmaceutical applications. The cefadroxil sulfoxide (CDSO) compound was synthesized and characterized by spectroscopic (FT-IR, FT-Raman, and UV–Visible) assessments. Computational investigations have been carried out concurrently with a B3LYP-6-311++G(d,p) basis set and density functional theory (DFT). The molecular vibrational assignments, chemical reactivity, electronic properties, and optical activities are calculated using gas and different solvent phases. The stable ground state configuration of the given molecular compound is investigated using PES analysis. Furthermore, the chemical behavior of the CDSO was thoroughly investigated for different solvent aspects through HOMO-LUMO, MEP, UV–Visible and electron-hole excitation analyses. The molecular occupancy, virtual occupancy, and overlapping bonding energies are investigated by TDOS, PDOS, and COOP spectrum studies. Fukui function and dual descriptor investigations extend to the chemical reactivity of individual atomic sites. The intra-molecular analysis provided a deeper understanding of the molecular interactions performed by natural bond orbitals (NBO) and non-linear optics (NLO), which provided optical activity for the title compound. Additionally, electron localization function (ELF), localized orbital locator (LOL), and reduced density gradient (RDG) analyses were also accomplished to provide insight into the delocalized orbitals in the header composite. The molecular docking was achieved, and the ligand with 4EVM protein is providing the potential antimicrobial biological activity (binding energy −7.12 kcal/mol) of the CDSO compound. [ABSTRACT FROM AUTHOR]

• Molecular geometrical parameters were calculated for the synthesised compound in the gas phase. • Spectroscopic characterizations (FT-IR,FT-RAMAN and UV–Vis) were performed and compared the interpretations with the simulated data. • HOMO-LUMO energies, MEP map, electron-hole distribution analysis was carried out for the different solvents. • ELF, LOL and RDG were estimated for the different solvents. • Drug-likeness and ADMET properties evaluation were discussed. • Docking analysis was performed for various targeted protein inhibitors. Chalcones are a significant class of naturally occurring chemical substances and their derivatives are extremely influential in the field of biological industries. In the current study, the title composite,4 - Chlorochalcone has undergone extensive investigation to understand its spectral properties using a combination of experimental and theoretical calculations. Fourier transform (FT-IR) infrared and FT-Raman characterizations provided valuable insights into the vibrational assignments (functional groups) in the header molecule, while ultraviolet–visible (UV–Vis) spectroscopy explored its electronic transitions and absorbance characteristics. The electronic properties were studied for the solvents viz., ethanol, methanol, DMSO, acetonitrile and benzene through theoretical-computational DFT calculations, revealing details about their molecular orbitals, electronic energies, and other energy parameters. Additionally, the NBO- natural bond orbital analysis shed light on the chemical bonding and electron distributions by donor and acceptor atoms. Furthermore, MEP- molecular electrostatic potential was analyzed for the various solvents and the calculated energy parameters were obtained. A drug-likeness evaluation was performed to assess its potential as a drug candidate based on its molecular properties. Moreover, the topological analysis and electron-hole distributions, contributed to a comprehensive understanding of electron density and localization within the molecule for the solvents viz., ethanol, methanol, DMSO, acetonitrile and benzene. Molecular docking investigations, as well as the Ramchandran plots, revealed that substituents targeting amino acids contribute to the antiviral action of the header compound. The potential of 4′-Chlorochalcone (ligand) as an antiviral agent offers promising prospects for further exploration and development in various therapeutic areas within the field of medicinal chemistry. [ABSTRACT FROM AUTHOR]

Ketorolac [(±)-5-Benzoyl-2, 3-dihydro-1H-pyrrolizine-1-carboxylic acid] have been investigated by experimental FTIR, FT-Raman, NMR and UV–Visible spectroscopy. The optimized molecular geometry and vibrational wave numbers were calculated by DFT combined B3LYP/6–311++G (d, p) basis set. The detailed vibrational assignments were carried out using VEDA program. Theoretical UV–Vis absorption spectrum was obtained in water using TD-DFT method. To determine the frontier molecular orbital energy gap and to confirm the electronic transition properties of the title molecule, the donor-acceptor (HOMO-LUMO), and for the intra molecular interactions NBO were studied. In order to get the precise chemical structure (shape and size) and reactivity, topology analyses were carried out. Further, the Non-Linear Optical (NLO) properties such as dipole moment, total linear and first order hyper polarizabilities have been studied to reveal the NLO nature. Also thermodynamic propertiess with respect to temperature were calculated. Considering the biological importance, pharmacological molecular descriptors have been computed. The anti inflammatory activity of the title compound docked into the active sites of the target protein was studied from docking parameters. Image 1 • Structural parameters were obtained by DFT-B3LYP method with higher basis set. • Comprehensive spectral analyses such as FTIR, FT-Raman, NMR and UV–Visible were reported. • Topology analyses on the surface of the title compound were carried out. • Charge transfer within molecule and chemical reactivity were reported. • Biological activity was revealed by molecular docking study. [ABSTRACT FROM AUTHOR]

In this present work, the molecule (2E)-1-(3-bromo-2-thienyl)-3-(4-chlorophenyl)-prop-2-en-1-one (3BCPO) has been synthesized and the molecular structure has been interpreted experimentally and theoretically in detail. Furthermore, the title molecule has been characterized by FT-IR, FT-Raman and UV–Vis spectroscopic techniques to have insight in its structural properties. Various methods of DFT (B3LYP, B3PW91and M062X) have been used through 6–311++G(d,p) basis set to optimize the structure of the title compound. Meanwhile, the optimized geometrical parameters, vibrational wavenumbers, electronic properties and Hirshfeld molecular surface analysis have also been performed. The electronic properties namely HOMO-LUMO, UV–Vis and MEP maps have been obtained by IEFPCM model with different solvation effects which is based on TD-DFT methods. The NLO activity of compound has been examined by gas and solvation methods. The donor and acceptor charge transfers mechanism has been explained by the natural bond orbital investigation. Molecular docking has been performed by the AutoDock 1.4.6 program to know the binding interactions of a ligand Interleukin 1 antagonist inhibitor (1ITB). In this present work, we reported a combined experimental and theoretical investigation on molecular structure, Spectroscopic(FT-IR, FT-Raman) studies of (2E)-1-(3-bromo-2-thienyl)-3-(4-chlorophenyl)-prop-2-en-1-one. The electronic properties namely HOMO-LUMO, UV–Vis and MEP maps have been obtained by IEFPCM model with different solvation effects which is based on TD-DFT methods. The NLO activity of compound has been examined by gas and solvation methods. The donor and acceptor charge transfers mechanism has been explained by the natural bond orbital investigation. Molecular docking has been performed by the AutoDock 1.4.6 program to know the binding interactions of a ligand Interleukin 1 antagonist inhibitor (1ITB). Image 1 • Spectral analysis of (2E)-1-(3-bromo-2-thienyl)-3-(4-chlorophenyl)-prop-2-en-1-one were investigated. • Solvational electronic properties UV–Vis, HOMO-LUMO, MEP and NLO activities were investigated. • The MEP and Hirshfeld surface have been discussed. • Molecular docking and Thermodynamical properties were analyzed at various temperatures. [ABSTRACT FROM AUTHOR]

In this present work, a molecule (2E)-3-(biphenyl-4-yl)-1-(4-bromophenyl) prop-2-en-1-one (3BPO) was synthesized and the structure has been characterized by using spectroscopic techniques. The most stable conformational structure of title compound has been calculated using HF-6-31G(d,p) basis set. DFT method were used through B3LYP/6–311++G(d,p) basis set to optimize the structure of the title compound. The geometrical parameters, vibrational wavenumbers and electronic properties have also been performed. The electronic properties for HOMO-LUMO, UV–Vis and MEP maps were contemplated by IEFPCM model with various solvation impacts which depends on TD-DFT ((M062X for UV and B3LYP for HOMO-LUMO, MEP)/6–311++G(d,p)) strategies. The NLO activity of title compound has been examined by solvation DFT/B3LYP technique with 6–311++G(d,p) premise set. Mean while, lone pair of donor-acceptor interactions and H bond donor/acceptor surface has been obtained by which a charge transfer mechanism can be explained. Molecular docking has been explored to comprehend the coupling transportation of the examined ligand with human folate receptor alpha in complex with folic corrosive protein (4LRH). In this present work, we reported spectroscopic studies, combined experimental and theoretical investigation on vibration frequency (FT-IR and FT-Raman), solvational electronic properties and molecular docking analysis of (2E)-3-(biphenyl-4-yl)-1-(4-bromophenyl) prop-2-en-1-one (3BPO). The structural stabilization energy, salvation electronic properties, HOMO-LUMO, NBO, NLO activities were analyzed and the biological evaluation of title compound has been explored to comprehend the coupling transportation of the examined ligand with human folate receptor alpha in complex with folic corrosive protein (4LRH). Image 1 • Stable conformer of 3BPO has been obtained by PES to analyze electronic, vibrational and biological properties. • Vibrational assignments were discussed by experimental and theoretical spectroscopic characterizations. • The electronic transitions and chemical reactions were explained by HOMO-LUMO, MEP, donor-acceptor surface. • Molecular docking was performed for human folate receptor, cancers inhibitor property of 3BPO. [ABSTRACT FROM AUTHOR]

• Synthesized, experimental and theoretical characterizations of 4CNB were performed. • FMO's, electronic properties, MEP map for different solvents elucidated. • NBO, Fukui function, Topology analyses (ELF, LOL) were estimated. • In silico analysis with different protein targets were examined. Being of the benzohyrazide derivatives, the molecule in consideration is quite significant in the pharmaceutical industry. In the present article, a novel compound has been synthesized and compared between the theoretical and experimental characterization such as FT-IR, UV–Vis and NMR techniques were employed. The quantum simulation studies (DFT) have been discussed for a higher basis set as B3LYP/6–311++G(d,p). Molecular vibrational assignments, chemical and electronic characteristics of 4-chloro-N -(2,6-dichlorobenzylidene) benzohydrazide (4CNB) were performed. The potential energy surface, geometrical optimization, wave numbers, and electronic structure stability were calculated by density function theory (DFT) through a higher basis set. The spectral characterizations of the molecule have been correlated with the observed spectrum. The chemical property of frontier orbital theory (FMO's) and electron-hole excitation analysis (D-index, Δr index,t index and excited states) for the different solvents such as DMSO, Chloroform, water and methanol were analysed. The DOS and orbital overlap functions were investigated. The stability of the structure, electrophilic and nucleophilic attacks for the different solvents, intra molecular analysis through NBO, molecular electrostatic potential (MEP) and local descriptors such as Fukui function (f+, f-, f0), topological analyses were performed and discussed. Molecular docking studies were performed by Auto-dock software to establish the information about the interactions between the antifungal and antibacterial inhibitor and lest binding energy is observed for Candida glabrata (−7.50 kcal/mol) protein. [ABSTRACT FROM AUTHOR]

Abstract A molecule 4-chloro-N-(4,5-dihydro-1H-imidazol-2-yl)-6-methoxy-2-methylpyrimidin-5-amine plays a significant role in the treatment of hypertension and acts as a potential I 1 imidazoline receptor agonist. In this present work, the molecular structure of the title compound has been investigated using experimental (FT-IR, FT-Raman and NMR) and theoretical (DFT) techniques. R2 values of FR-IR, FT-Raman and bond lengths state the coherence between theoretical and experimental values. Asymmetric, symmetric stretching and bending vibrations were reported. The geometrical parameters obtained theoretically are in agreement with experimental values. Chemical activity region of the molecule (MEP), molecular stability, charge localization and delocalization (NBO), occupied and unoccupied molecular orbitals (HOMO-LUMO), dipole moment, polarizability and hyperpolarizability (NLO) have been calculated. There is a significant change in a net atomic charge distribution with a corresponding increase in the value of total dipole moment. Furthermore, the mulliken population analysis on atomic charges (electronic properties), thermodynamic parameters at various temperatures have also been calculated. To study the biological activity, different proteins for ligand have been taken and the results suggest that the compound might exhibit anti-hypertensive activity. Henceforth, Quantum mechanical calculations have been done for the title compound to get optimized structure and electronic energies for biological, physical, pharmaceutical and medicinal interest. Graphical abstract Image 1 Highlights • Spectroscopic interpretation of 4NDIM5 has been carried out. • HOMO–LUMO energies and dipole moment have been obtained. • Local reactivity using Fukui function, NBO and MEP diagram were computed and analyzed. • Molecular docking and Drug-likeness were also discussed. [ABSTRACT FROM AUTHOR]

In this work, FT-IR, FT-Raman and UV–vis spectra of 1 Phenyl Isatin (1PHISA) were carried out by using HF/6-31++G(d,p) and DFT/B3LYP method with 6-31++G(d,p),6-311++G(d,p) basis sets. The geometric parameters and wavenumbers were obtained and the complete assignments of fundamental vibrations were performed on the basis of potential energy distribution (PED) of the vibrational mode, calculated with scaled quantum mechanics (SQM) method. The hyper conjugative interaction leading to the stability of the molecule and delocalization of charge has been analyzed with natural bond analysis (NBO). HOMO-LUMO energy calculations show the charge transfer within the molecule. Molecular electrostatic potential, hyper polarizability calculations and thermodynamic functions of the compound were also calculated. The biological applications of 1PHISA have been screened out for antimicrobial activity such as antibacterial and antifungal activities. Molecular docking studies were also carried out for different receptors. [ABSTRACT FROM AUTHOR]

The research exploration will comprise of investigating the molecular structure, vibrational assignments, bonding and anti-bonding nature, nonlinear optical, electronic and thermodynamic nature of the molecule. The research is conducted at two levels: First level employs the spectroscopic techniques - FT-IR, FT-Raman and UV–Vis characterizing techniques; at second level the data attained experimentally is analyzed through theoretical methods using and Density Function Theories which involves the basic principle of solving the Schrodinger equation for many body systems. A comparison is drawn between the two levels and discussed. The probability of the title molecule being bio-active theoretically proved by the electrophilicity index leads to further property analyzes of the molecule. The target molecule is found to fit well with Centromere associated protein inhibitor using molecular docking techniques. Higher basis set 6-311++G(d,p) is used to attain results more concurrent to the experimental data. The results of the organic amine 2, 4 Dibromoaniline is analyzed and discussed. [ABSTRACT FROM AUTHOR]

Theoretical and experimental FT-IR and FT-Raman vibrational spectral analysis of 6-[(2- methylphenyl) sulfanyl]-5-propylpyrimidine-2,4(1H,3H)-dione have been recorded in the region 4000- 400 cm-1 and 4000-100 cm-1 in solid phase. The molecular geometric parameters bond length, bond angle and vibrational wave numbers, as well as harmonic vibrational frequency were investigated using the density functional theory B3LYP method with the 6-311++G(d,p) basis set. The stability of the molecule has been investigated using the natural bond orbital (NBO) analysis. The electronic properties such as HOMO-LUMO energies were determined by the time-dependent DFT approach. The thermodynamic properties and the first order hyperpolarizability and molecular electrostatic potential (MEP) of the title compound were also studied. The electron density-based local reactivity descriptors such as the Fukui functions were calculated to explain the chemical selectivity or reactivity site in the molecule. The molecule orbital contributions were investigated using the total density of states (TDOS), the sum of α and β electron density of states (αβDOS). The molecular docking (ligand-protein) simulations have been performed using the AutoDock 4.2.6. Binding energy, bonded residues and donor-acceptor bond length values revealed that title compound can act as potential inhibitor against HIV-1 protease. [ABSTRACT FROM AUTHOR]

• PES, molecular geometrical parameters were calculated for three phases (Gas, polar protic and aprotic solvents). • HOMO-LUMO energies, MEP map, electron-hole distributions have been carried out. • QTAIM, ELF, LOL and RDG analyses were estimated. • Drug-likeness and ADMET properties were discussed. • Molecular docking studies was performed for various targeted AKT inhibitors proteins. The theoretical elucidation of 1-(tert‑Butoxycarbonyl)-3-piperidinecarboxylic acid (1TB3PC) was achieved in this work by using DFT/6–311++ G (d,p) as the basis set level -B3LYP approach for the gas phase, polar aprotic, and protic solvents phases, respectively. Potential energy scan (PES) analysis and the optimized geometrical parameters for the gas, polar aprotic and polar protic solvent phases were attained and corresponding parameters were compared with the closely related molecule. The FMO's molecular orbitals (HOMO-LUMO) and the energy gap, FLU indices, and molecular electrostatic potential map (ESP) surface were carried out to predict the nucleophilic and electrophilic regions for the three phases (gas, polar aprotic, and polar protic solvents) were discussed. Further, the electron-hole distribution for the excited states and topological analyses (AIM, ELF, LOL and RDG) were also deliberated. To discern the biological activity of the title compound, drug likeness and ADMET predictions were carried out. Molecular docking approach was performed against ligand with various AKT /Protein Kinase B inhibitors targets and their corresponding parameters were conferred. Thus, the header composite designates as an alternative anticancer therapeutic agent. [Display omitted] [ABSTRACT FROM AUTHOR]

• Vibrational assignment carried out. • FOM theory, UV-Visible and DOS spectra are investigated. • Hirshfeld surface, NBO, NLMO, NHO and MEP are analyzed. • Drug- likeness, ADMET, and molecular docking investigation. The title compound, (2E)-3-(Biphenyl-4-yl)-1-(2,4-dichlorophenyl)-prop-2-en-1-one (BPDC) has been derived from the compounds namely biphenyl-4-carbaldehyde and 2,4-dichloroacetophenone to perform 3D-Potential energy conformations for molecular stability by DFT calculation of B3LYP/6-311++G(d,p). The geometrical optimization and atoms vibrational spectral data observed FT-IR and FT-Raman spectra values were compared with theoretical values (B3LYP, CAM-B3LYP). The molecule was characterized by absorbed infrared radiation, scattered Raman techniques with the attention on important functional groups (Cl, O, N). Electro negativity difference has been discussed and their biochemical and biomedical properties have been examined. The chemical reactivity of the compound was characterized by MEP-map, NHO, NLMO, and NBO analyses. The frontier molecular orbital (HOMO–LUMO) energy gap, vertical electron truncation of UV–Visible spectrum, and their λ-max value have been compared with CAM-B3LYP and M062X/6-311++G(d,p) approach data. The orbitals arrangements were studied by the density of states (DOS) and the partial density of states (PDOS). BPDC is investigated by Hirshfeld surface analysis that employs three-dimensional contours and two-dimension fingerprint area for intermolecular interactions quantitatively. The biological investigations like drug-likeness and toxicity properties of BPDC molecule were conformed to Lipinski's rule of five and ADMET properties, respectively. The title molecule exhibits a good bioactive score and less toxicity. Antibacterial and also antifungal activities of BPDC were done by docking analysis. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

• The experimental values of 1B4NAP are in agreement with theoretical results. • MEP map, HOMO-LUMO energies, AIM, ELF, LOL were estimated. • Fukui function, thermodynamically parameters were discussed. • VEGFR-2 Kinase Inhibitor - an anti-cancer therapy was examined using molecular docking interaction studies. In the present study, 1-Benzyl-4-(N-Boc-amino)piperidine was characterized by spectroscopic investigations employing FT-IR, FT-Raman, UV-Vis and NMR (13C, 1H) techniques. The optimized geometrical parameters and complete vibrational assignments of frequencies based on Potential Energy Distribution (PED) were determined by using Density Functional Theory (DFT) through the B3LYP and dispersion correction method WB97XD with the level of 6-311++G(d,p) basis set and compared with the experimental values. The Potential Energy Scan (PES) studies have been employed to investigate the conformational preference of the molecule. Besides, to gain better insight on structural features of title composite, HOMO-LUMO bandgap energy and electron excitation analysis was obtained. Molecular Electrostatic Potential (MEP) energy surface and Fukui function descriptor using NPA (Natural Population Analysis) charges were employed to investigate the most reactive sites of the title compound. Natural bond orbital analysis (NBO) elucidates the delocalization of charge due to intramolecular interactions. The topological studies (AIM, ELF and LOL) and thermodynamic parameters at different temperatures were performed. The anticancer activity of header compound against VEGFR-2 Kinase inhibitor receptors for different protein targets (6GQO, 6GQP, 4AG8 and 1Y6B) was studied using molecular docking. Image, graphical abstract [ABSTRACT FROM AUTHOR]

2-acetylthiophene (2ATP) and its bromination compound 2-acetyl-5-bromothiophene (2A5BTP) were characterized by FT-IR, FT-Raman and UV–Vis experimental techniques. By using Gaussian 09 software, the complete vibrational analysis 2-acetylthiophene (2ATP) was carried out and compared with experimental values. Here all the theoretical calculations were carried out by DFT technique with B3LYP method and 6-311++G(d,p) basis set. BY using the UV–Vis spectrum the electronic transition is observed and compared with the simulated Time-dependent (TD-DFT) method. From the frontier molecular orbital calculation, the HOMO-LUMO gap was found to be 4.9664 eV and 4.6091 eV for the compounds 2ATP and 2A5BTP respectively. The exchange of charges within the molecule is obtained using Natural Bond Orbital analysis (NBO). The interaction energy and bonding type can be observed by Atoms in molecules (AIM) theory with the aid of multiwfn software. The reactive areas of 2ATP and 2A5BTP were obtained from Molecular Electrostatic Potential (MEP) and Fukui function studies. The Non-linear optical (NLO) properties were also analyzed for the above two compounds by DFT methods. The biological properties and drug design were obtained by ADME and molecular docking methods. Image 1 • Vibrational spectral studies. • Reactive areas by Fukui function. • AIM, NBO and NLO studies. • Drug-Likeness and Molecular docking. [ABSTRACT FROM AUTHOR]

The bromo based theyophen chalcone derivative 1-(3-Bromo-2-thienyl)-3-[4-(dimethylamino)-phenyl] prop-2-en-1-one (BTDAP) has been investigated by spectroscopy and quantum chemistry methods using Gaussian09 software package. The stable conformation of molecular structure, vibrational frequencies and electronic absorption spectra were established using B3LYP/6-311++G(d,p) and M062x/6-311++G(d,p) calculations. The Infrared intensities, Raman scattering active regions have been calculated. UV–Visible absorption spectrum has showed the best agreement with their experimental results. The formation of the donor and the acceptor stabilization energies, molecular bonding which is composed from orbitals that have been localized on different atoms and molecular bond angular properties were investigated using NBO, NLMO and NHO calculations. Frontier molecular orbital analysis which explains the energy gap between the ground state HOMO and first excited state LUMO energies were determined. Besides, the chemical properties of condensed Fukui function, MEP and electron-hole charge transfer within the molecule due to excitation for three excited states were obtained by multiwfn software. Molecular docking studies were performed for the title compound with Monoamine oxidase A and B inhibitions. In this present work, the bromo based theyophen chalcone derivative of 1-(3-Bromo-2-thienyl)-3-[4-(dimethylamino)-phenyl] prop-2-en-1-one (BTDAP), we reported stable conformation of molecular structure, vibrational frequencies and electronic absorption spectra were established using B3LYP/6-311++G(d,p) and M062x/6-311++G(d,p) calculations. The Infrared intensities, Raman scattering active regions have been calculated. UV–Visible absorption spectrum has showed the best agreement with their experimental results. The chemical and electronic properties of NBO, NLMO and NHO calculations, Frontier molecular orbital, condensed Fukui function, MEP and electron-hole charge transfer within the molecule due to excitation for three excited states were obtained by multiwfn software. Molecular docking studies were performed for the title compound with Monoamine oxidase A and B inhibitions. • In this work, conformation behaviors of PES and molecular structure stability were studied. • Vibrational wave numbers are assigned using PED analysis. • The chemical reactivity was analyzed by NBO, HOMO-LUMO and Condensed Fukui Function. • Molecular docking studies are reported. [ABSTRACT FROM AUTHOR]

Chalcone derivative of (2E)‑1‑(3‑bromo‑2‑thienyl)‑3‑(2,5‑dimethoxyphenyl) prop‑2‑en‑1‑one (BTD) molecule has been deliberated for spectroscopic properties experimentally and theoretically. The title compound was characterized by FT-IR, FT-Raman and UV–Vis analyses. The structural activity and vibrational wavenumbers were calculated by a DFT method. The Natural Bond Orbital (NBO) analysis which reveals the hyper conjugative interactions of the present molecule has been performed. Meanwhile, the Chemical reactivity of Condensed Fukui function, MEP and HOMO-LUMO energies of the molecule were also analyzed. Furthermore, Multiwfn 3.3.9 program has been utilized to study MEP and the electron excitation analysis. Docking studies which play a significant role in determining the endothelial nitric oxide synthase inhibition activity of the present compound have also been carried out to predict the binding energy and inhibition constant of the title compound. In addition, drug resemblance parameters have also considered by QSAR study in which the comparison of chemical parameters of chalcone drugs of title molecule has been done. Unlabelled Image • In this work, conformation behaviors of PES and molecular structure stability was studied using DFT/ B3LYP/6-311++G(d,p) method. • FT-IR and FT-Raman vibrational assignments are performed on the basis on the PED • The HOMO-LUMO, MEP and Global chemical reactivity were investigated. • Protein-ligand interactions were analyzed. • Quantitative Structure-Activity Relationship studies that establish relationship between chemical descriptors and eNOS inhibition. [ABSTRACT FROM AUTHOR]