Hirshfeld Surface Studies Research Articles

Synthesis, SC-XRD, DFT Investigation and Hirshfeld Surface Analysis of 1-Neopentyl-2,4,5-Triphenyl-1H-Imidazole Derivatives

The title compounds 5a and 5b were synthesized and characterized by FT-IR, 1H and 13C NMR, UV-Vis spectral techniques. The compound 5b is confirmed by single-crystal XRD. Compound 5b belongs to the triclinic system with space group P-1. The compound 5b unit cell parameters are a = 6.0629 (2) Å, b = 12.3831 (4) Å, c = 15.2890 (5) Å. Moreover, Hirshfeld surface studies have been evaluated by two-dimensional fingerprint plots and applied the percentage of interactions involved in the formation of the crystal packing. Compounds 5a and 5b theoretical studies were also recorded using the density functional theory method. Experimental values are well supported by theoretical studies.

Exploration of experimental, theoretical, Hirshfeld surface, molecular docking and electronic excitation studies of Menadione: A potent anti-cancer agent

In this report, experimental, Computational analysis of menadione (2 methyl-1,4 nathoquinone) has been carried out theoretically by (DFT) density functional theory using B3LYP method with 6-311++G (d,p) basis set. Vibrational spectroscopic study and various other parameters have been accomplished. AIM theory (Atoms in molecules) is used to calculate the ellipticity, iso-surface projection by electron localization function, and binding energies. The computational theoretical spectra of FT-IR showed great agreement with the experimental results. A detailed description of crystal surface intermolecular interactions was carried out and Hirshfeld surface analysis, fingerprint plots were drawn via crystal explorer software. The NBO study helped in analyzing the donor and acceptor interaction. The nucleophilic and electrophilic interactions of the molecule were determined by the Fukui function and Molecular Electrostatic Potential (MEP). TD-DFT with PCM model was done with different solvents. Exploration of electron excitation from occupied to unoccupied orbitals in a single pair of electrons takes place. With DMSO and MeOH as solvents, hole and electron density distribution maps (EDD and HDD) were drawn in an excited state. The HOMO → LUMO energy gap showed the strength and stability of the molecule. With the help of the electrophilicity index and other parameters, the biological potency of the molecule is theoretically estimated. The drug-likeness was also studied and molecular docking was done using different proteins and with binding energy −9.5, −8.3, and −6.2. The biomolecular stability was investigated using a molecular dynamics simulation.

Synthesis, Characterization, Crystal Structure, Hirshfeld Surface, Electronic Excitation, Molecular Docking, and DFT Studies on 2-Amino Thiophene Derivative

Ethyl-2-amino-5,6,7,8-tetrahydro-4H-cyclo-hepta[b]thiophene-3-carboxylate (EACHT) has been synthesized, characterized via single-crystal X-ray diffraction at 293 K and investigated quantum chemically by DFT approach, surface analysis by Hirshfeld and spectrochemically by NMR (1H-NMR and 13C-NMR), FTIR, and UV–Visible. The compound crystallizes in monoclinic crystal system with P21/c space group with Z = 4, with following unit cell dimensions: a = 9.5956 (3) Å, b = 9.5607 (4) Å, c = 13.7226 (7) Å. To get the optimized structure which is base for all the other calculations (vibrational frequency, NBO, natural hybrid orbital, nonlinear optical, frontier molecular orbital, etc.), B3LYP method with 6-311++G(d,p) basis set was used. Complete potential energy distribution assignments were done successfully by VEDA. 1H-NMR and 13C-NMR shifts were estimated by GIAO method and results were compared with experimental spectra. TDDFT method and PCM solvent model was utilized for electronic property analysis such as UV–Vis (in gas phase, ethanol, and DMSO) and compared with the experimental UV–Vis spectra. The HOMO and LUMO energy results emphasize adequate charge transfer was happened within the molecule. NBO analysis MEP surface analysis electron localization function Diagram and Fukui function analysis were done. Hole and Electron density distribution maps were drawn in two different excited states of higher oscillatory strength with DMSO, MeOH as solvents. Docking with seven different receptors, and drug likeness was also carried out.

Growth, THz properties, and Hirshfeld surface studies of 4-N,N-dimethylamino-4- N-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate single crystal

Growth, THz properties, and Hirshfeld surface studies of 4-N,N-dimethylamino-4- N-methyl-stilbazolium 2,4,6-trimethylbenzenesulfonate single crystal

Synthesis, Crystal Structure, Spectroscopic and Hirshfeld Surface Study of a New Functionalized Α-Hydroxyphosphonate Complex of Tin (IV) Chloride

Synthesis, Crystal Structure, Spectroscopic and Hirshfeld Surface Study of a New Functionalized Α-Hydroxyphosphonate Complex of Tin (IV) Chloride

Synthesis, molecular structure, Hirshfeld surface, energy framework and DFT studies of 1,3,4 oxadiazole derivative

1,3,4 oxadiazoles and their derivatives exhibit significant biological properties like anti-tumor, anti-fungal, anti-bacterial, analgesic, and anti-inflammatory activities. The title compound, N-(2-bromophenyl)-5-phenyl-1,3,4-oxadiazole-2-amine was synthesized in good yield. The product was characterized by spectroscopic techniques (1H NMR, UV–Vis). The crystal structure of the compound was established by single crystal X-ray diffraction study. The compound crystallizes in the monoclinic crystal system in the space group P21/c. Prediction model (2D fingerprint model and Hirshfeld surface) was performed to understand the intermolecular interactions responsible for molecular packing and the strength of molecular packing in the crystal. From the 3D molecular energy frameworks, the total interaction energy was calculated. Further, DFT calculations were performed to correlate the results with experimental results. The static and dynamic linear polarizability (α), first dipole hyperpolarizability (β), and second dipole hyperpolarizability (γ) were calculated using DFT/B3LYP method.

Synthesis, crystal structure, Hirshfeld surface, DFT and docking studies of 4-[(5‑hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(phenyl)methyl]-5-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one

In the present work, 4-[(5‑hydroxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)(phenyl)methyl]-5-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (BPZ) was synthesized by one pot multicomponent reaction of ethylacetoacetate, phenylhydrazine and benzaldehyde in the presence of Ce-MCM-48 catalyst. The title compound was characterized by FT-IR, 1H NMR, and 13C NMR spectral studies and single crystal XRD technique. The intermolecular contacts of the title compound were studied by Hirshfeld surface (dnorm surfaces and 2D fingerprint plots) analysis whereas an intra-molecular hydrogen bonding interaction was examined through NCI-RDG plot. The geometry of the molecular structure was optimized by using the density functional theory (DFT) at B3LYP/6–311 g(d,p) level. Molecular electrostatic potential (MEP), natural bond orbital (NBO) analysis, nonlinear optical properties (NLO) and global chemical reactivity parameters (GCRP) were described through computational method. Further, the molecular docking study was done for title compound with COVID-19 caused protein structure (6LU7, nCoV-SARS-2 Mpro). The study revealed that the significant conventional hydrogen bonding and other interactions were observed between the active amino acid residue of SARS-nCoV-2 Mpro and BPZ ligand.

Synthesis, crystallization, XRD, Hirshfeld surface, vibrational spectra, and quantum chemical studies and Computational investigation of Caffeinium bisulfate: a new noncentrosymmetric form

Crystals of caffienium bisulfate were grown by solution growth technique. The vibrational spectra were scaled by adopting FT-IR and FT-Raman spectroscopy with the wide range, between 4000-400 cm−1. X-ray diffraction study exhibited that the functional group such as N-H….O hydrogen bonds played an effective role in generating hydrogen-bonded crystal packing, pre-dominant. The examined molecules showed an interconnection of anions, by the O-H…O hydrogen bonds, establishing a chain C (4) motif, extending along the b-axis of the unit cell. Further, anions have shown interaction with cations, through N-H…O hydrogen bond, resulting from a ring R1 2 (4) motif. The formed ring and chain motifs manifested an alternate hydrophilic stratum at z = ¼ and ¾. Geometrical optimization of tester molecule was done with Density Functional Theory (DFT) employing B3LYP function along with Hartree-Fock (HF) using 6-311++G(d,p) level basis set. Optimum molecular geometry and calculated database on the vibrational spectra were critically analyzed by comparing with experimental findings, resulting in a good correlating exhibited among them. Natural Bond Orbital (NBO) study revealed that hyper conjugation affinities and intermolecular charge transfer (ICT). An advanced technique such as HOMO-LUMO plot was performed to understand the chemical hardness, electro negativity and chemical efficacy of the tested molecules. The results showed that the occurrence of lower band gap value in the frontier orbital was responsible for the possible biological activities of the study materials. Bioinformatics analysis is applied for analyzing the biological activity of CAFSUL against Alzheimer's disease through computational methods. Communicated by Ramaswamy H. Sarma

Crystal structure elucidation and DFT studies of imidazopyridine-pyrazoline derivative

The present work concentrates on the newly synthesized imidazopyridine-pyrazoline derivative. The compound is characterized by LC-MS, Infrared (IR) analysis, and X-ray diffraction. The molecule crystallizes in the monoclinic crystal system with the space group P21/n. The unit cell parameters are: a = 4.8410(12) Å, b = 17.065(4) Å, c = 23.332(7) Å, α = γ = 90°, and β = 92.390° Hirshfeld surface study was carried out to quantify the intermolecular interactions and crystal packing. The geometry optimization was done using the density functional theory (DFT) calculations using B3LYP hybrid functional. Theoretical calculations such as energy gap between the frontier molecular orbitals, molecular electrostatic potential surface and non covalent interactions were studied.

Synthesis, Spectral, Crystal structure, Hirshfeld surface, Computational analysis, and Antimicrobial studies of Ethyl-(E)-4-(2-(2-arylidenehydrazinyl)-2-oxoethyl)piperazine-1-carboxylates

A new series of ethyl-(E)-4-(2-(2-arylidenehydrazinyl)-2-oxoethyl)piperazine-1-carboxylates (hydrazones) 4a-4e and 5a-5c were designed and synthesized from 1-ethoxycarbonylpiperazine. The hydrazones structure interpretations were achieved by spectroscopic analysis using FT-IR, 1D and 2D NMR and mass. Among the aforementioned hydrazones 4a-4e and 5a-5c, single crystal XRD structure was reported for hydrazone 4a. Both NMR and single crystal XRD analysis are clearly indicated the existence of E configuration of the azomethine group (-C=N-) and cis conformation of the amide group. Hirshfeld surface analysis and 2D fingerprint plot were employed to get a better understanding of non-covalent interactions (NCIs), which showed that the NH···O and CH···O intermolecular hydrogen bonding interactions are the key contributor to stabilize the molecular solids. Density functional theory (DFT) study was carried out to explore the geometrical parameters and electronic properties of frontiers molecular orbitals (FMO), global chemical reactivity descriptor parameter (GCRD), natural bond orbital (NBO), and non-linear optical (NLO) properties for 4a at B3LYP/6–311G(d,p) level. The molecular docking study was performed for hydrazone 4a with nCoV-SARS-2 main protease for COVID-19. Finally, the hydrazones in this synthetic series were screened for their antibacterial and antifungal activities using selected strains. Antimicrobial studies revealed that 4a and 5b against A. niger, 4c and 5c against K. pneumonia, 4e against B. subtilis, 5a, 5b, and 5c against A. flavus, A.niger and C. neoformans, respectively exhibits remarkable antibacterial and antifungal activity at a minimum concentration of 6.25 µg/mL.

Structure, hirshfeld surface studies, optical and mechanical analysis on a third-order nonlinear optical crystal 2-amino-6-methylpyridin-1-ium 2-chloro-4-nitrobenzoate (2A6M2C4N)

Organic third order nonlinear optical material, 2-Amino-6-methylpyridin-1-ium 2-chloro-4-nitrobenzoate (2A6M2C4N) was effectively synthesized and single crystals were developed by slow cooling solution growth method. The crystallographic structure of the grown crystal has been confirmed through single crystal X-ray diffraction analysis and it uncovers that the title material belongs to Triclinic crystal system with centrosymmetric space group of P-1. The crystalline phase formation was ascertained from powder X-ray diffraction measurements. The functional groups present in the compound were confirmed by Fourier transform infrared analysis. Optical analysis explicit that the grown crystal possess good transmittance in the wave length region of 200–800 nm. Photoluminescence spectroscopy analysed by exciting the material at 320 nm supports that 2A6M2C4N crystal suits the requirements of optoelectronic devices. The thermal behaviour of 2A6M2C4N exploited by TG-DTA measurements show that it is stable up to 160.04 °C. Third order nonlinear optical properties such as nonlinear refractive index and third order nonlinear optical susceptibility were calculated by employing the z-scan technique. The HOMO-LUMO, molecular electrostatic potential (MESP) and contour map of the molecule was examined at B3LYP/6–311++G (d, p) level by using DFT calculations. The existence of the intermolecular interactions in the molecule were confirmed by Hirshfeld surface studies. • Novel third order nonlinear optical crystals 2A6M2C4N has been grown by slow cooling technique. • 2A6M2C4N belongs to triclinic crystal system with centrosymmetric space group P-1. • Intermolecular-interactions in 2A6M2C4N molecule were characterized by Hirshfeld surface analysis. • Third order nonlinear optical susceptibility (χ(3)) was calculated to be 2.918 × 10–11 esu.

One-pot synthesis, Spectral, X-ray crystal structure, Hirshfeld surface and computational study on potential inhibitory action of novel 1-benzyl-2-(4-methoxynaphthalen-1-yl)-4,5-diphenyl-1H-imidazole derivatives against COVID-19 main protease (Mpro: 6WCF/6Y84)

A novel compound of 1-benzyl-2-(4-methoxynaphthalen-1-yl)-4,5-diphenyl-1H-imidazole (BMNDPI) are conveniently synthesized and characterized by spectral analysis FT-IR, 1H NMR, 13C NMR, Mass spectral and density functional theory (DFT/B3LYP/6–31 G (d, p) computations. The compound BMNDPI was also confirmed by single crystal XRD. The calculated geometric parameters are consistent with XRD data. To explore the intermolecular interactions, the generated Hirshfeld surface has been investigated along with 2D-fingerprint plots. The NBO results reflect the charge transfer is mainly by the orbital overlap between n (LPN54/LPO56) and σ * C1-N55/C43-C48 bond orbital which results intra-molecular charge transfer (ICT) causing stabilization of the system. Stability and charge transfer within the compound was explained by frontier molecular orbital calculations. Atomic charges on the various atoms of BMNDPI obtained by Mulliken population analysis. Potential reactive sites of the BMNDPI compound have been identified by MEP which is mapped to the electron density surfaces. The reported molecule is used as a potential NLO material since it has a high μβ0 value. The molecular docking mechanism between BMNDPI ligand and COVID-19/6WCF and COVID-19/6Y84 receptors were studied to investigate the binding modes of these compounds at the active sites. Molecular docking outcomes have shown that the BMNDPI molecule can be considered as a potential agent against COVID-19/6WCF-6Y84 receptors.

Synthesis, crystal structure, Hirshfeld surface analysis and theoretical investigation of polynuclear coordination polymers of cobalt and manganese complexes with nitrobenzene and pyrazine

Herein, two new cobalt and manganese-based polymers named as catena‑Poly[[diaquabis(4-nitrobenzoato-κO1)cobalt(II)]-µ-pyrazine-κ2N:Nʹ] (COPNO2) and catena‑Poly[[diaquabis(4-nitrobenzoato-κO1)manganese(II)]-µ-pyrazine–κ2N:Nʹ] (MNPNO2) were synthesized. The crystal structure of COPNO2 and MNPNO2 was determined and explored by X-rays diffraction method. OH⋯O, CH⋯π, NO⋯π, and π⋯π stacking interactions were the key aspects of the crystal packing of COPNO2, whereas for MNPNO2, OH⋯O, CH⋯π, and π⋯π stacking interactions were the key aspects of the crystal packing. The Hirshfeld surface (HS) studies were accomplished for further investigation of the intermolecular interactions. In addition to that, density functional theory (DFT) computations for COPNO2 and MNPNO2 had been carried out at M06 functional, to obtain optimized geometries and double-check the experimental results. Moreover, DFT calculations at the M06 level manifest excellent correlation with the experimental data, which validates the clarity of cobalt and manganese-based polymers. Frontier molecular orbital (FMO) findings were explored to describe nonlinear optical (NLO) properties. The energy gap of COPNO2 was 0.81 eV, while MNPNO2 was examined as 2.16 eV. The global reactivity parameters of COPNO2 and MNPNO2 were determined from the FMO energies. The global reactivity parameters showed that COPNO2 and MNPNO2 have the more donating ability. The NLO results of MNPNO2 (βtot = 1259.17178a.u.) were observed better than COPNO2 (βtot = 34,678.44833a.u.). We propose that this synergistic (experimental-computational) study of COPNO2 and MNPNO2 may deliver new ways for its exploitation as NLO material for hi-tech applications.

Exploring the Noncovalent Interactions of the Dinuclear Cu(II) Schiff Base Complex with Bovine Serum Albumin and Cell Viability against the SiHa Cancer Cell Line.

In the present study, a dinuclear bis(μ-acetate) dicopper(II) complex [Cu2L2(μ1.1-CH3COO-)2] has been synthesized from a tridentate NNO Schiff Base ligand L (L = 2,4-dibromo-6-((3-(methylamino)propylimino)methyl)phenol) and characterized by elemental, ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR), 1H NMR, and electrospray ionization-mass spectrometry (ESI-MS) spectroscopic studies. The single-crystal X-ray structure, different noncovalent interactions, Hirshfeld surface analysis, and density functional theory (DFT) studies of the dinuclear complex were determined by crystallographic computational studies. The structural study exposed that the complex consists of the penta-coordinated double μ1.1-acetato-bridged dinuclear units of Cu(II), and it is a centrosymmetric dimer in which the center of inversion lies at the midpoint of two Cu(II) ions. Hirshfeld surface and DFT studies pointed out the probable potentiality of the crystal in prospective binding with the protein. This was experimentally verified by carrying out the binding interaction studies against bovine serum albumin (BSA) protein using various spectroscopic methods. It was observed that the copper(II) complex could strongly bind to BSA and could quench the intrinsic fluorescence of BSA. Further, the studied complex was appraised for cell viability studies against SiHa cancer cells. It is observed that cell viability increases with time, demonstrating the biocompatible nature of the complex.

Synthesis, computational, spectroscopic, hirshfeld surface, electronic state and molecular docking studies on diethyl-5-amino-3-methylthiophene-2,4-dicarboxylate

Diethyl 5-amino-3-methylthiophene-2,4-dicarboxylate (DAMC) was synthesized, characterized, and investigated theoretically and by experimental spectroscopy. Surface analysis by Hirshfeld, and Spectrochemical analysis by NMR (1H NMR and 13C NMR), FT-IR, and UV–Visible were performed. 1H NMR and 13C NMR shifts were estimated by the GIAO method and results were compared with experimental spectra. The energy difference between HOMO and LUMO revealed the chemical activity of the titled molecule such as Ionization Energy, Electron Affinity, Electronegativity. The molecular docking was carried out with 12 different protein receptors on a molecule to find the best ligand–protein interactions. Drug-likeness was also carried out.

Stereochemical, single crystal X-ray structural, Hirshfeld surface and cyclic voltammetric studies of N-cyclohexylcarbamoyl-3-isopropyl-2,6-bis(phenyl)piperidin-4-one and N-cyclohexylcarbamoyl-3,3-dimethyl-2,6-bis(4-fluorophenyl)-piperidin-4-one

• Twist boat conformation of N -cyclohexylcarbamoylpiperidin-4-one was proved by NMR and XRD. • Single crystal X-ray structural and Hirshfeld surface analysis of 1 and 2 were performed. • Computational and cyclic voltammetric studies were also performed. N- Cyclohexylcarbamoyl-3-isopropyl-2,6-bis(phenyl)piperidin-4-one (1) and N- Cyclohexylcarbamoyl-3,3-dimethyl-2,6-bis(4-fluorophenyl)piperidin-4-one (2) were synthesized and characterized by IR, 1 H NMR, 13 C NMR, HOMOCOSY, NOESY, HSQC and HMBC. Single crystal X-ray diffraction study was performed for 1 and 2 . Both the compounds (1 and 2) crystallized in triclinic crystal system with P -1 space group. From the XRD analysis results it is observed that the conformation of the heterocyclic ring in 1 and 2 is twist boat. The computational study was performed and the structures were optimized using DFT – B3LYP with the 6 - 31G basis set. Hirshfeld surface analysis was also carried out and the contributing intermolecular interactions which stabilizes the crystal structures are quantified. It exemplifies the predominant contribution of van der Waals interaction in the packing of both the crystal structures. Cyclic voltammetric studies were also performed and discussed. From the CV analysis it is observed that 2 exhibit the high specific capacitance value even at higher scan rate.

Experimental and computational studies on the synthesis and structural characterization of 2-(4-chlorophenoxy)-N-[4-(4-methylphenyl)-1,3-thiazol-2-yl]acetamide

The title compound 2-(4-chlorophenoxy)-N-[4-(4-methylphenyl)-1,3-thiazol-2-yl]acetamide (3) has been achieved via a sequence of multistep synthesis processes in good yield started by 2-(4-chlorophenoxy)acetic acid (1) with 4-(4-methylphenyl)thiazol-2-amine (2) in dry dichloromethane followed by the addition of lutidine, and O-(benzotriazole-1-yl)-N,N,N',N'-tetramethyluroniumtetrafluoroborate as coupling agent in cold condition to accomplish (3). The synthesized compound was elucidated by different spectroscopic techniques (NMR and LC-MS) and finally, the structure was confirmed by X-ray diffraction method. The title compound has crystallized in the orthorhombic crystal system with the space group Pca21. Density functional theory calculations were carried out to compare the computational values of (1) and (2) with (3). The frontier molecular orbitals (HOMO-LUMO) and molecular electrostatic potential (MEP) of (3) were analyzed. In the crystal structure, intermolecular and intramolecular interactions were observed. Atom N12 represents the chiral center of (3) which is connected to four different groups. The stereochemistry of this molecule at N12 is S configuration. Hirshfeld surface studies and 2D fingerprint plots neatly quantify the interactions involved within the structure. Energy frameworks analysis for (3) were performed through different intermolecular interaction energies to understand the packing of molecules and to determine the type of the dominant energy.

Non covalent interactions and molecular docking studies on morphine compound

The (5α,6α)-7,8-didehydro-4,5-epoxy-17-methylmorphinan-3,6-diol (morphine)molecule has been studied using the density functional theory and molecular docking methods and non covalent interactions. The conformational analysis of the molecule at the B3LYP/6−311++G** and HF/6−311++G** levels has been made. The comparison of the structural parameters computed using the B3LYP function with the experimental data has revealed their good agreement. The weak intermolecular interactions in the morphine structure have been analyzed using several techniques. The Hirshfeld surface study has been carried out to identify the diverse intermolecular interactions (mainly hydrogen bonds) and the … π stacking interactions. The analysis of the topological (AIM, ELF, LOL) and non covalent (RDG, IRI, DORI) interactions has revealed different categories of inter- and intramolecular contacts on the basis of the electron localization density and color scale indicator, respectively. The molecular docking study has been carried out to examine the possibility of biological application of the title conformer using the 1DLO (cancerous), 2BK3 (Parkinson), 3LN1 (inflammatory), 4HOE (microbial), and 5 K95 (schizophrenia) enzymes. The analysis has shown that the morphine structure can be used not only in analgesia, but also in the treatment of diseases. The investigated compound has shown good results with monoamine oxidase B (MOAB) at a score of −105.04 kcal/mol.

Quantum computational, spectroscopic, Hirshfeld surface, electronic state and molecular docking studies on sulfanilic acid: An anti-bacterial drug

Sulfanilic acid (SAA) has been studied experimentally and theoretically. The DFT approach (Density functional theory) is used for theoretical investigations. Hirshfeld analysis was used for 3D and 2D surface analysis, while NMR (1H NMR and 13C NMR), FT-IR, and UV–Visible spectra were used for spectrochemical study. All of the experimental spectroscopic analyses came back with results that were quite close to the calculated values. To explore electron excitation from occupied to unoccupied orbitals in a single pair of electrons, Hole and Electron density distribution maps (EDD and HDD) were drawn in an excited state with DMSO and MeOH as solvents. The B3LYP method with a 6-311++G(d,p) basis set was utilised to obtain the optimized structure on which all other computations (vibrational frequency, NBO, NHO, NLO, FMO, etc.) are based. The 3D description of intermolecular interactions of crystal surface was done by Hirshfeld surface analysis and while fingerprint plots were used to describe the 2D interactions, SAA was stabilized by formation of H---H/O---H/C---H contacts. VEDA was effectively implemented for total potential energy distribution. The electron localization function was used to examine the Atom-In-Molecule theory (AIM) for determining binding energy, ellipicity, and isosurface projection. The hybridizations of generated bonds, the interference energy, and the interactions between donor and acceptor are all revealed by NBO analysis. The reactive areas of the molecule were defined using Fukui functions and the molecular electrostatic potential (MEP). Charge transfer was revealed in the UV–Vis spectrum, which was computed using TD-DFT/PCM methods with various solvents. At various temperatures, thermodynamic parameters such as free energy, enthalpy, and entropy were calculated. By calculating the electrophilicity index, the bioactive probability of the molecule was theoretically proven. Molecular docking was used to explore protein-ligand interactions, and the lowest binding energy was found to be −6.4 kcal/mol. SAA was also subjected to drug-likeness investigation including its derivatives and all compounds were discovered to have a similar nature. As a result, this molecule could be utilized in the development of drugs.

Quantum Chemical, experimental spectroscopic, Hirshfeld surface and molecular docking studies of the anti-microbial drug Sulfathiazole

Sulfathiazole (ST) was investigated quantum chemically by DFT approach, surface analysis by Hirshfeld and experimentally by NMR (FT-IR, UV-Visible 1H-NMR and 13C-NMR). The B3LYP method and the 6-311 ++ G (d, p) basis set were applied to optimize the molecular structure and to calculate the wavenumbers of normal vibrational modes. A detailed description of the intermolecular interactions of the crystal surface was carried out by means of Hirshfeld surface analysis and fingerprint plots found. SF is a powerful antimicrobial drug and also falls into the sulfonamide category and is one of the major building blocks in the pharmaceutical sector. The calculated bond lengths and angles were compared with the experimental bond lengths and bond angle parameters and found to be in good agreement. VEDA successfully carried out complete tasks for the distribution of potential energy. 1H-NMR and 13C-NMR shifts were estimated using the GIAO method and the results compared with experimental spectra. The TD-DFT method and the PCM solvent model were used for the analysis of electronic properties such as UV-Vis (in gas phase, ethanol and DMSO) and compared with the experimental UV-Vis spectra. The HOMO / LUMO energy results emphasize that sufficient charge transfer occurs within the molecule. The donor-acceptor connections were investigated by means of NBO analysis. The MEP surface analysis was carried out to show the charge distribution in the molecule. The degree of relative localization of electrons was analyzed using the FLF diagram. The Fukui functional analysis to find possible points of attack for various substituents and the surface of the molecular electrostatic potential (MEP) was created for the 3-D color representation. The analysis of intermolecular interactions over the Hirshfeld surface showed that ST is primarily stabilized by the formation of S — H / O — H / H — H / H — N / C — H contacts has been. The biological study like molecular docking was carried out with 17 different receptors in order to find the best ligand-protein interactions and the similarity with the active substance.