Spectroscopic (FT-IR, FT Raman) and quantum mechanical study on N-(2,6-dimethylphenyl)-2-{4-[2-hydroxy-3-(2-methoxyphenoxy)propyl]piperazin-1-yl}acetamide

Synthesis and Spectroscopic Characterization of Schiff Base Metal Complexes, Biological Activity, and Molecular Docking Studies

New cobalt(II), copper(II), and zinc(II) Schiff metal complexes were synthesized by the condensation reaction of 4-nitrobenzene-1,2-diamine with 3-4-(diethylamino)-2-hydroxybenzaldehyde. Fourier transform infrared, nuclear magnetic resonance, ultraviolet-visible, electron paramagnetic resonance, and high-resolution electrospray ionization mass spectrometry and powder X-ray diffraction were used to characterize the synthesized H2L and its metal complexes. Conductance measurements, magnetic moment estimation, and metal estimation have all been determined and discussed. The electrochemical properties of the synthesized compounds have been determined and discussed using cyclic voltammetry. The molecular structures of H2L and its metal complexes have been optimized using the B3LYP functional and the 6-31G (d,p) basis set, and their parameters have been discussed. The quantum chemical properties of these synthesized compounds have been predicted through charge distribution and molecular orbital analysis. The biological properties of the synthesized compounds' antioxidant, antifungal, and antibacterial activity have been studied and discussed. Furthermore, H2L and its complexes have been docked with HER2-associated target proteins in breast cancer.

Bonding and noncovalent interactions effects in 2,6-dimethylpiperazine-1,4-diium oxalate oxalic acid: DFT calculation, topological analysis, NMR and molecular docking studies

The pharmaceutical proprieties of the 2,6-dimethylpiperazine-1,4-diium oxalate oxalic acid compound have been studied and the relevant drug design has been considered. The investigated organic compound with formula (2,6-(CH3)C4H10N2)2(C2O4)2·H2C2O4 (2DPOA) has been synthesized by slow evaporation technique at room temperature of a molar ratio 3:2 mix of oxalic acid and 2,6-dimethylpiperazine. Then 2DPOA has been characterized by IR, 13C NMR, UV–visible and the DFT calculation at the B3LYP level of theory has been made. The molecular structure and parameters (bond angles and lengths) of the molecule have been optimized using the Gaussian 09 software and compared with the XRD data. The atoms-in-molecules (AIM), electron localization function (ELF), and localized orbital locator (LOL) methods have been utilized to determine the types and nature of noncovalent interactions present within the 2DPOA molecule. These methods offer insights into the characteristics and behavior of these interactions. Furthermore, the presence of these interactions has been confirmed through the Hirshfeld Surface (HS) and reduced density gradient (RDG) analysis. The NBO analysis is employed to assess the charge exchange occurring within the studied compound. The molecular reactive sites have been examined using the molecular potential surface and Mulliken atomic charges. The energy gap between HOMO–LUMO and chemical properties of 2DPOA have been determined within the frontier molecular orbital theory. The UV–Vis spectrum of the 2DPOA molecule has been recorded and examined. The calculated and experimental infrared absorption and nuclear magnetic resonance spectra of 2DPOA molecule have been investigated. Finally, the molecular docking simulation has been used to find novel inhibitors and drugs for the cancer and epilepsy disease treatment.

Conformation and vibrational spectroscopic analysis of 2,6-bis(4-fluorophenyl)-3,3-dimethylpiperidin-4-one (BFDP) by DFT method: A potent anti-Parkinson's, anti-lung cancer, and anti-human infectious agent

The potential of 2,6-bis(4-fluorophenyl)-3,3-dimethylpiperidin-4-one (BFDP) as an anti-Parkinson's, anti-lung cancer, and anti-human infectious agent was extensively assessed in the current study. To accomplish this, the compound BFDP was synthesised and analysed using several spectroscopic approaches, such as NMR, mass and FT-IR spectral studies. The computational calculations for the molecule were carried out using density functional theory (DFT) at the B3LYP/6-311G++ (d,p) level of theory. A X-ray diffraction (XRD) study allows us to analyse the crystalline structure of our BFDP molecule. Intermolecular interactions were assessed using 3D Hirshfeld surfaces (3D-HS) and 2D fingerprint plots. AIM and NCI-RDG were done using quantum calculations and the DFT technique, and topological ELF and LOL, as well as vibrational parameters, have been obtained. The thermodynamic and thermal properties of the BFDP compound were determined. To investigate the pharmacokinetic characteristics of BFDP, a molecular docking study and an in silico ADMET study were done.

Theoretical and experimental spectroscopic studies and analysis for wave function on N-phenylmorpholine-4-carboxamide benzene-1,2-diamine with computational techniques

The present study focuses on structural and chemical analyses of N-phenylmorpholine-4-carboxamide benzene-1,2-diamine (PMCBD) using quantum computational methods. The calculated bond angle, length, and dihedral angle between atoms were compared with measured values. The observed and stimulated FT-IR (Fourier Transform Infrared Spectroscopy) spectra parameters for vibrational wavenumbers and their associated PED (Potential Energy Distribution) values in percentage have been obtained from VEDA4 software. The electronic transitions of PMCBD were discussed by TD-SCF/DFT/B3LYP based on the 6-311++G(d,p) basis set with solvents such as chloroform, ethanol, and dimethyl sulfoxide (DMSO) and gas. Density functional computations were used to study the band energy between HOMO and LUMO using the B3LYP/6-311++G(d,p) level. Mulliken analysis and natural population analysis were used for a better understanding of charge levels on different atoms such as N, H and O. The natural bonding orbital (NBO) analysis proved helpful in studying molecular and bond strengths. (NBO). The ESP acquired data on the molecule's size, shape, charge density distribution, and chemical reactivity site. This was done by mapping electron density on the surface with electrostatic potential. Non-linear optical detection of PMCBD was also discussed. Aside from the electron localization function map, state densities are also mapped using Multiwfn software, a wave function analyzer.

Antiureolytic activity of new water-soluble thiadiazole derivatives: Spectroscopic, DFT, and molecular docking studies

Two new water-soluble thiadiazole compounds are prepared and characterized with various techniques. These compounds, 5-amino-1,3,4-thiadiazole hydrochloride (1) and 5-amino-3-(N-propane-2-imine)-1,3,4-thiadiazole chloride salt (2) were synthesized via Mannich reaction, and characterized by microelemental analysis, and some spectroscopic means (FTIR, UV-Vis, ¹H NMR, ¹³C NMR and mass), in addition to single-crystal X-ray diffraction for compound 2. DFT calculations were conducted to study their geometry optimization, vibrational spectra, MEP maps, and NBO analysis. In addition, TD-DFT calculations were performed to study their absorption spectra. The prepared compounds were tested against Jack beans urease enzyme (in vitro) to indicate their antiureolytic activity potency. The activity of the enzyme was measured under optimal conditions, before and after mixing with the prepared organic compounds. The results showed that both compounds have potentially inhibited the enzyme activity with respect to their IC₅₀ values: 13.76 µM ± 0.15 for 1, and 18.81 µM ± 0.18 for 2. These values are even lower than that of thiourea (21.40 ± 0.21 µM) as a standard inhibitor. The inhibition activity of urease enzyme was confirmed by a Lineweaver-Burk plot. According to the kinetic parameters obtained from the Lineweaver-Burk plot, the inhibition of urease enzyme by compounds 1 and 2 seems to be non-competitive. Molecular docking studies of the prepared compounds 1 and 2 were performed in order to interpret the obtained biological results and to investigate their interactions with the urease enzyme active site. These studies reveal that compounds 1 and 2 are good candidates as inhibitors for urease enzyme. Moreover, compound 1 exhibits a higher promising inhibition activity.

Exploring the molecular structure, vibrational spectroscopic, quantum chemical calculation and molecular docking studies of curcumin: A potential PI3K/AKT uptake inhibitor

The IUPAC name of curcumin is (1E, 6E)-1,7-Bis(4-hydroxy-3methoxyphenyl) hepta-1,6-e-3,5-dione (7B3M5D) and is characterized by spectroscopic profiling with FT-IR and FT-Raman spectra obtained both experimentally and theoretically. PED analysis was done for the confirmation of minimum energy obtained in the title compound. Optimized geometrical parameters are compared with experimental values obtained for 7B3M5D by utilizing B3LYP functional employing 6–311++G (d,p) level of theory. The HOMO-LUMO, MEP, and Fukui function analysis has been used to elucidate the information regarding charge transfer within the molecule. The stabilization energy and charge delocalization of the 7B3M5D were performed by NBO analysis. This article assesses that the title compound act as a potential inhibitor of the PI3K/AKT inhibitor through in silico studies, like molecular docking, molecular dynamics (MD), ADMET prediction and also this molecule obeys Lipinski's rule of five. 7B3M5D was docked effectively in the active site of PI3K/AKT inhibitor.

Vibrational spectra, Hirshfeld surface analysis, molecular docking studies of (RS)-N,N-bis(2-chloroethyl)-1,3,2-oxazaphosphinan-2-amine 2-oxide by DFT approach

The Cyclophosphamide (CYC) is used as an anti cancer agent. It is chemically known as (RS)-N,N-bis(2-chloroethyl)-1,3,2-oxazaphosphinan-2-amine 2-oxide. The vibrational assignments survey of the CYC was implemented by employing FT-IR and FT-Raman spectroscopic investigation and the results are compared with theoretical features. The optimized geometrical parameters, IR intensity and Raman Activity of the vibrational bands of CYC were determined from the B3LYP functional with 6-311++G (d, p) level of theory. In the current work, quantum chemical calculations were adopted to contemplate the vibrational assignments of CYC and the outcomes are compared with experimental findings. Molecular Electrostatic Potential (MEP) and HOMO-LUMO energies are very effective in the examination of charge transfer and distribution of the molecular structure. The molecular orbital contributions were evaluated by using the Total Density of States (TDOS). The analysis of Natural Bond Orbital (NBO), Mulliken population and Fukui function studies were done. Intermolecular interaction of the title compound was examined through Hirshfeld surface analysis. The evaluation of drug-likeness was accomplished in accordance with Lipinski's Rule of Five and molecular descriptors were utilized to predict the ADMET profiles of the CYC molecule. The recent research studies reports that the structural and bio-activity of the CYC was affirmed by the docking analysis of CYC with protein PI3K/AKT inhibitor, it acts as anti-lung cancer agent.

Spectroscopic elucidation (FT-IR, FT-Raman and UV-visible) with NBO, NLO, ELF, LOL, drug likeness and molecular docking analysis on 1-(2-ethylsulfonylethyl)-2-methyl-5-nitro-imidazole: An antiprotozoal agent

1-(2-ethylsulfonylethyl)-2-methyl-5-nitro-imidazole (1EMI) C₈H₁₃N₃O₄S also known as Tinidazole, selected for its antiprotozoal property is extensively used for spectroscopic elucidations and computational aspects using density functional methods. Along with spectral conclusions, further investigations on fundamental reactive properties such as electrical, optical, nonlinear combined with DFT simulations were performed. Molecular docking procedure supports the results of chosen appropriate antiprotozoal agent based on ligand-protein interactions. Experimental and simulated (B3LYP/6-311++G (d,p)) IR and Raman spectra showed concurrence. NLO analysis through first order hyperpolarizability parameter helps in finding the potential of 1EMI as a good NLO candidate. Charge delocalization and the stability of the compound were discussed using natural bond orbital (NBO) analysis. Furthermore, Electron localization function (ELF), local orbital locator (LOL), and Frontier molecular orbitals (FMO) were studied. Besides, Mulliken population analysis on atomic charges, Energy gap, chemical potential, global hardness, softness, ionization potential, electronegativity, electrophilicity index along thermodynamic parameters (enthalpy, entropy and heat capacity) have been calculated. Drug likeness parameters and molecular docking approach enabled to check pharmaceutical potential and biological activity of 1EMI. The biological activity of 1EMI through ligand and protein interactions have been confirmed theoretically for the treatment of Malaria, Invasive aspergillosis and Mycobacterium tuberculosis with respect to chosen proteins. Three different activity targets and protein interactions are quite successful revealing the bond distances, intermolecular energy, binding energy and inhibition constant. 2D interaction profile image of the two maximum interacted proteins and also Ramachandran plot used to show stereochemistry of selected protein. The activities of 1EMI were studied in accordance with literature survey and the results were presented.

Synthesis, characterization and biological investigations of potentially bioactive heterocyclic compounds containing 4-hydroxy coumarin

In this paper, we have reported the synthesis of a series of heterocyclic azo dyes containing 4-hydroxy coumarin by diazo-coupling reaction. The structural aspect of the newly synthesized compounds was accomplished by various physico-chemical techniques like UV-Visible, FT-IR, NMR, and mass spectrometry. The computational calculations and geometrical optimization of the newly synthesized azo dyes were investigated by using Gaussian software with the help of Density functional theory (DFT)/B3LYP method using 6-31G(d,p) basis set at gaseous phase. Also, the quantum chemical parameters were evaluated to understand the structural activity concept of the dyes. The pharmacological efficacy of the azo dyes was investigated by antimicrobial, antitubercular, DNA cleavage and in silico molecular docking studies. All the newly synthesized compounds were able to exhibit significant inhibitory activity against tested microbes. Further, the in silico molecular docking showed effective binding properties of the compounds against RpsA target receptor.

Spectroscopic and quantum computational study on naproxen sodium

The spectroscopic (FT-IR, FT-Raman, NMR), electronic (UV--Vis.), structural and thermodynamical properties of an anti-inflammatory analgesic called Naproxen Sodium, (s)-6-methoxy-α-methyl-2-naphthaleneacetic acid sodium salt are submitted by using both experimental techniques and theoretical methods as quantum chemical calculations in this work. The equilibrium geometry and vibrational spectra are calculated by using DFT (B3LYP) with 6-311++G (d,p) basis set using GAUSSIAN 09. The vibrational wavenumbers are also corrected with scale factor to take better results for the calculated data. The HOMO-LUMO calculations are carried out on the title compound. The theoretical and experimental NMR peaks were found to be in good agreement. In addition, the detailed study on the Non-Bonding Orbitals, the excitation energies, AIM charges, condensed fukui calculations, thermodynamical properties, Localized Orbital Locator (LOL) and Electron Localization Function (ELF) are also performed. Furthermore, the study is extended to calculate the first order hyperpolarizability and to predict its NLO properties. The docking studies details helped on predicting the binding with different proteins.

Molecular docking, spectroscopic studies on 4-[2-(Dipropylamino) ethyl]-1,3-dihydro-2H-indol-2-one and QSAR study of a group of dopamine agonists by density functional method

Density functional theory is one of the most popular accepted computational quantum mechanical techniques used in the analysis of molecular structure and vibrational spectra. Experimental and theoretical investigations of the molecular structure, electronic and vibrational characteristics of 4-[2-(Dipropylamino) ethyl]-1,3-dihydro-2H-indol-2-one are presented in this work. The title compound was characterized using FT-IR, FT-Raman and UV-Vis spectroscopic techniques. The results were compared with the theoretical calculations obtained using DFT/B3LYP with 6-311++G(d,p) as basis sets and was found to be in good agreement. The complete optimization of the molecular geometry of the title compound was carried out. Further, the vibrational assignments and calculation of potential energy distribution (PED) were reported. NLO has emerged as a key factor in recent researches. Materials showing nonlinear optical properties form the basis of nonlinear optics and development of such materials plays an important role in the present scenario. The current work provides sufficient justification for the title compound to be selected as a good non-linear optical (NLO) candidate. The electronic properties were reported using TD-DFT approach. The HOMO (EHOMO = -5.96 eV), LUMO (ELUMO = -0.80 eV) energies, energy gap and electrophilicity (2.22) was calculated in order to understand the stability, reactivity and bioactivity of the compound under investigation. To comprehend the bonding interactions we have performed the total (TDOS), partial (PDOS) and overlap population or COOP (Crystal Orbital Overlap Population) density of states. The drug likeness values were analyzed to evaluate the potential of the title compound to be an active pharmaceutical component. As a positive proof the paper further explains the molecular docking studies of the said compound. In addition, the stereochemistry of the protein structure was checked using Ramachandran plot. The title compound is a directly acting dopamine D2 agonist. In order to establish relationship between molecular descriptors of compound and its biological activity, QSAR studies have been done within the framework of DFT for 10 dopamine agonist including the title compound. Hence, the research exploration provides requisite information pertaining to the geometry, stability, reactivity and bioactivity of the compound through spectroscopic and quantum chemical methods.