Yazar "Ashfaq, Muhammad" seçeneğine göre listele

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    A comparative study of X-ray structural analysis, supramolecular investigation by Hirshfeld surface analysis and DFT computations for tricyclic 1,4-benzodiazepines
    (Elsevier, 2025) Kurbanova, Malahat; Ahsin, Atazaz; Aliyev, Gaya; Ashfaq, Muhammad; Sahin, Onur; Tahir, Muhammad Nawaz; Abuelizz, Hatem A.
    The tricyclic 1,4-benzodiazepines - seven-membered heterocyclic compounds were synthesized derived from the three-component reaction involving o-phenylenediamine, 5,5-dimethyl-1,3-cyclohexanedione and various aromatic aldehydes under the influence of HCl. The crystal structure of 11-(3-nitrophenyl)-3,3-dimethyl2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]diazepin-1-one (NDDD) and 11-(2-chlorophenyl)-3,3-dimethyl2,3,4,5,10,11-hexahydro-1H-dibenzo[b,e][1,4]diazepin-1-one (CDDD) corroborated through single crystal X-ray diffraction method. The Hirshfeld surface analysis indicates crystal packing along with role of intermolecular forces in stabilizing supramolecular assembly of NDDD and CDDD. 2D fingerprint analysis is carried out to envisage to the elemental interactions in the assumption of a single crystal containing molecular fragments. DFT investigations have been carried out to understand the reactivity of NDDD and CDDD at the m062x/def2tzvp method. The obtained geometric parameters from theoretical study are well consistent with experimentally reported XRD analysis. Bonding analysis and charge transfer were examined by performing quantum theory of atoms in molecules (QTAIM) and natural bonding orbital (NBO) analysis. The synthesized NDDD and CDDD exhibit excellent electronic and nonlinear optical properties. The NLO response is justified through computed hyperpolarizability values.
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    Crystalline salt synthesis from p-dimethylaminobenzaldehyde and o-phenylenediamine, single crystal XRD study along with computational investigation
    (Elsevier, 2025) Kurbanova, Malahat; Ashfaq, Muhammad; Ahsin, Atazaz; Sahin, Onur; Sayida, Shoubova; Maharramov, Abel; Tahir, Muhammad Nawaz
    The condensation reaction of p-dimethylaminobenzaldehyde with o-phenylenediamine under the gaze of CCl3COOH results in the synthesis of 2-(4-(dimethylamino)phenyl)- 1H-benzo[d]imidazole-3-ium chloride (DBIC) crystalline salt. The X-ray diffraction method confirms that DBIC is crystallized in monoclinic crystal system with space group P21/n and chemical formula 2(C15H16N3)+0 & sdot;2(Cl)-& sdot;H2O. XRD showed that DBIC is a salt with asymmetric unit composed of two cations, two anions and a water molecule. Difference between the orientation of two cations concerning each other is explored by molecular overlay plot. N-H & ctdot;O, N-H & ctdot;Cl, OH & ctdot;Cl, C-H & ctdot;Cl, C-H & ctdot;pi, pi & ctdot;pi intermolecular interactions stabilize the solid-state assembly which are explored via Hirshfeld surface analysis. The H & ctdot;H and H & ctdot;Cl are the most dominating elemental contacts within the crystal structure. DFT study reveals the superb electronic structures and reactivity of DBIC. The presence of noncovalent interactions between Cl-atom and H-atoms of cationic moiety can impart excellent NLO features in our complex. The molecular electrostatic potential and electron localizing function predicts the surface reactivity and bonding electrons in complex. The optical and nonlinear optical properties were anticipated through hyperpolarizability response.
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    First crystalline salt of 1,1-bis-(carboxymethylthio)-1-phenylethane: synthesis, crystal structure, Hirshfeld surface analysis, and computational study
    (Taylor & Francis Ltd, 2026) Osmanova, Sabiya; Kurbanova, Malahat; Ambreen, Jaweria; Ashfaq, Muhammad; Tahir, Muhammad Nawaz; Sahin, Onur; Shah, Khizar Hussain
    The reaction of 1,1-bis-(carboxymethylthio)-1-phenylethane with piperidine was conducted in an acetone solution at a molar ratio of the initial components of 1:2. As a result, a new compound was obtained: piperidinium-1,1-bis-(carboxymethylthio)-1-phenylethane, characterized by FT-IR. The crystal structure of the synthesized compound is structurally elucidated via single crystal XRD technique, indicating that a H-atom is transferred from half of the piperidinium-1,1-bis-(carboxymethylthio)-1-phenylethane part to the piperidine ring and the structure is a salt in nature. N-H & ctdot;O and C-H & ctdot;O bondings contribute to the stability and enforcement of crystal packing; further assessment is supported via Hirshfeld surface analysis, considering interatomic contacts. We employed density functional theory (DFT)-based computations along with molecular dynamics (MD) simulations in a systematic manner, aiming for the investigation of the stabilizing interactions and electronic characteristics of the molecular ionic compound. The structural framework is notably stabilized by dual N-H & centerdot;& centerdot;& centerdot;O hydrogen bonding, originating from piperidine rings positioned on either side of the central fragment. Electronic structure analysis revealed intermolecular charge transfer characteristics through HOMO-LUMO orbital distributions, complemented by TD-DFT studies of excited state behavior. Furthermore, ab initio MD simulations at 300 K conclusively demonstrated the ionic compound's robust kinetic and dynamic stability.
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    Single crystal XRD, Hirshfeld surface analysis and computational approach for exploration of novel xanthene derivative
    (Elsevier, 2025) El Bakri, Youness; Kurbanova, Malahat; Ahsin, Atazaz; Gurbanova, Fidan; Ashfaq, Muhammad; Sahin, Onur; Tahir, Muhammad Nawaz
    In order to study the structure-activity relationship of xanthene compound, hexahydro xanthene derivative was synthesized and characterized by single crystal X-rays diffraction. The molecular geometry was described in terms of dihedral angles between various rings present in structure. The stability of the supramolecular assembly was reinforced by multiple intermolecular interactions, which were inspected comprehensively via Hirshfeld surface analysis. DFT study revealed the excellent electronic properties and reactivity of synthesized compound. FMO is employed to uncover the orbitals energies and charge transfer within compound. The contribution of van der Waals forces is minor, while covalent nature of bonding is evidenced by the quantum theory of atoms in molecules (QTAIM) study. The electron transition from nonbonding orbitals (LP) to antibonding (LP*) are most prominent donor-acceptor interactions with significant stabilization energy. Ab-initio molecular dynamics reveals the kinetic and thermodynamic stability of present compound at room temperature. The excellent nonlinear optical properties and reactivity is revealed by its remarkable hyperpolarizability value.
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    Sulfaguanidine-based schiff bases, synthesis, crystal structure, FT-IR, hirshfeld surface analysis, and concise computational study
    (Springer/Plenum Publishers, 2026) Iqbal, Alqadar; Tahir, Muhammad Nawaz; Ali, Asghar; Feizi-Dehnayebi, Mehran; Bilal, Hazrat; Munawar, Khurram Shahzad; Ashfaq, Muhammad
    The current work reports the synthesis of three new sulfaguanidine-based Schiff bases: (E)-N-(diaminomethylene)-4-((2-hydroxy-3-methoxybenzylidene)amino)benzenesulfonamide (DHMB), (E)-N-(diaminomethylene)-4-((2,4-dichlorobenzylidene)amino)benzenesulfonamide (DCLB), and (E)-N-(diaminomethylene)-4-((4-fluoro-2-hydroxybenzylidene)amino)benzenesulfonamide (DFHB). The synthesized derivatives were initially characterized by FT-IR spectroscopy to confirm the presence of the azomethine linkage (HC = N), a characteristic aspect of Schiff bases. Then, single-crystal XRD analysis was performed for structural elucidation. The structures of DHMB and DFHB adopt the enol tautomeric form, stabilized by intramolecular O-H & ctdot;N hydrogen bonding, whereas DCLB did not exhibit tautomerism. DFHB exists in a solvated form, while the other structures are non-solvated. Hirshfeld surface analysis reveals several intermolecular interactions, which contribute to the stabilization of the compounds in the solid state. Furthermore, molecular docking simulations and DFT calculations were employed to explore the structural, biological, and electronic characteristics of the synthesized derivatives. The HOMO-LUMO energy gap analysis indicated that DHMB has the highest reactivity, with a gap of 3.97 eV. Molecular docking against the HER2 kinase domain demonstrated that DHMB possesses the strongest binding affinity (-8.92 kcal/mol). Overall, DHMB displayed enhanced electronic properties and biological potential, suggesting its promise as a lead compound for HER2-targeted anticancer drug development.
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    Synthesis and description of intermolecular interactions in new sulfonamide derivatives of tranexamic acid
    (Elsevier, 2016) Ashfaq, Muhammad; Arshad, Muhammad Nadeem; Danish, Muhammad; Asiri, Abdullah M.; Khatoon, Sadia; Mustafa, Ghulam; Zolotarev, Pavel N.
    Tranexamic acid (4-aminomethyl-cyclohexanecarboxylic acid) was reacted with sulfonyl chlorides to produce structurally related four sulfonamide derivatives using simple and environmental friendly method to check out their three-dimensional behavior and van der Walls interactions. The molecules were crystallized in different possibilities, as it is/after alkylation at its O and N atoms/along with a co-molecule. All molecules were crystallized in monoclinic crystal system with space group P2(1)/n, P2(1)/c and P2(1)/a. X-ray studies reveal that the molecules stabilized themselves by different kinds of hydrogen bonding interactions. The molecules are getting connected through O-H center dot center dot center dot O hydrogen bonds to form inversion dimers which are further connected through N-H center dot center dot center dot O interactions. The molecules in which N and 0 atoms were alkylated showed non-classical interaction and generated centro-symmetric R-2(2)(24) ring motif. The co-crystallized host and guest molecules are connected to each other via O-H center dot center dot center dot O interactions to generate different ring motifs. By means of the ToposPro software an analysis of the topologies of underlying nets that correspond to molecular packings and hydrogen-bonded networks in structures under consideration was carried out. (C) 2015 Elsevier B.V. All rights reserved.
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    Synthesis, crystal structure, supramolecular assembly inspection via hirshfeld surface analysis and computational investigation of the pyrimethamine-based salts
    (Elsevier, 2025) Tahir, Muhammad Nawaz; Malik, Abida Naseem; Ashfaq, Muhammad; Munawar, Khurram Shahzad; Rashid, Zahid; Imran, Muhammad
    In current research work, two salts abbreviated as 5DECA and 2DECA derived from pyrimethamine and aceclofenac are synthesized by using a simple method of reflux in methanol. The crystal structures of salts are investigated by the single-crystal X-ray diffraction (SC-XRD) technique. The supramolecular architecture of both compounds contained N-H & ctdot;O, N-H & ctdot;N, C-H & ctdot;O, off-set it & ctdot;it stacking, and C-O & ctdot;it interactions. The difference in supramolecular architecture is that in 5DECA, O-H & ctdot;O and C-H & ctdot;it interactions are present, whereas in 2DECA, N-H & ctdot;Cl, C-H & ctdot;Cl, and C-Cl & ctdot;it interactions are present. The presence of water molecule in 5DECA is the main reason for the difference between the supramolecular architecture of compounds. The intermolecular interactions in terms of interatomic contacts are probed by Hirshfeld surface analysis (HSA). Void analysis is performed to understand the mechanical response of crystals. Computational studies, conducted at the DFT/ B3LYP//ma-def2-SVP level of theory, confirmed that the supramolecular assemblies in these systems are governed by it-it and N-H & ctdot;O interactions. These calculations also determined several key factors, comprising structural features, molecular electrostatic potential (MEP), the HOMO-LUMO energy gap (Delta E), and Infrared spectroscopic absorption peaks.
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    Synthesis, structural exploration, Hirshfeld surface analysis and computational study of two novel organosulfur compounds derived from mercaptoacetic acid
    (Elsevier, 2026) Osmanova, Sabiya; Ashfaq, Muhammad; Kareem, Rebaz Obaid; Tahir, Muhammad Nawaz; Azeez, Yousif Hussein; Omer, Rebaz Anwar; Sahin, Onur
    The reaction of 2-aminopyridine with mercaptoacetic acid was carried out in a benzene solution at a molar ratio of the initial components of 1:1. The thiylated reaction of p-bromoacetophenone with mercaptoacetic acid was carried out in a benzene solution, with a molar ratio of the initial components of 1:4. As a result, new compounds were obtained: 2-aminopyridin-1-ium-2,2 '-disulfanediyldiacetate (ASA) and 1,1-bis-(carboxymethylthio)-1-p-bromophenylethane (BSA). The structure of the newly synthesized compounds was confirmed by using single crystal XRD technique. The structure of ASA is a salt in which there exist two cations and one dianion in the asymmetric unit. The cations and dianions are interlinked by N-H & sdot;& sdot;& sdot;O and C-H & sdot;& sdot;& sdot;O bonding and further stabilization of the crystal packing is due to weak pi & sdot;& sdot;& sdot;pi and C-O & sdot;& sdot;& sdot;pi interactions. In second compound BSA, molecules are interlinked in the form of dimers through O-H & sdot;& sdot;& sdot;O bonding to complete two R22(8) loops and consecutive dimers are connected by C-H & sdot;& sdot;& sdot;Br bonding. Hirshfeld surface analysis is carried out for the exploration of the molecular interactions in terms of interatomic contacts. The theoretical investigation of two related organic compounds, ASA and BSA, using density functional theory (DFT) and related computational tools to evaluate their structural, electronic, and intermolecular interaction properties. Optimized geometries, frontier molecular orbitals (HOMO-LUMO), electrostatic potential (ESP) maps, and dipole moments were obtained using the B3LYP/6-311+G(d,p) level of theory. The analysis of electron localization function (ELF), reduced density gradient (RDG), and topological parameters (via QTAIM) provided insights into electron density distribution, hydrogen bonding, and interaction strengths within the molecules. Hirshfeld surface analysis was performed using Crystal Explorer to explore intermolecular interactions and visualize contact contributions in the crystal state. The findings suggest that ASA, with its higher dipole moment, lower energy gap, and stronger electrophilic nature, exhibits superior potential as a corrosion inhibitor compared to BSA.
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    Synthesis, structural features, computational study along with molecular docking examination of organosulfur mercaptoacetic acid based compound
    (Springer/Plenum Publishers, 2025) Osmanova, Sabiya; Kurbanova, Malahat; Ashfaq, Muhammad; Feizi-Dehnayebi, Mehran; Tahir, Muhammad Nawaz; Sahin, Onur
    We carried out a thiylating reaction of p-nitroacetophenone with thioglycolic acid. The reaction was carried out in a benzene solution, with a molar ratio of the initial components of 1:4. 1,1-bis-(carboxymethylthio)-1-p-nitrophenylethane (CTNE). Structural features are evaluated via Fourier transform infrared (FT-IR) spectroscopy, 1H NMR and single crystal X-ray diffraction (XRD) analysis. Structure is composed of an organosulfur molecule and a water molecule. Organosulfur molecule adopted non-planar conformation supported via dihedral angle of 71.3 (4)degrees among carboxylic acid groups. Supramolecular organization is primarily supported via O-H & ctdot;O bonding. Further stability of the supramolecular organization is due to pi & ctdot;pi interactions with inter-centroid separation range from 3.85 to 4.01 & Aring;. Strong and weaker interactions are evaluated via Hirshfeld surface analysis which showed that H & ctdot;O contact has highest contribution in stability of the supramolecular organization. DFT calculations at the B3PW91/6-311 + + g (2d,2p) level was employed to optimize the molecular geometry and assess the electronic properties of the synthesized compound. Highest Occupied Molecular Orbital (HOMO)- Lowest Unoccupied Molecular Orbital (LUMO) energy gap (triangle E = 4.06 eV) of the synthesized compound indicates enhanced chemical reactivity and biological potential compared to precursor molecules. Furthermore, molecular docking studies demonstrated a promising binding affinity (-7.05 kcal/mol) toward VEGFR2, stabilized through hydrogen bonding and hydrophobic interactions, suggesting potential anticancer activity through angiogenesis inhibition.
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    Synthesis, structure, supramolecular assembly inspection by Hirshfeld surface analysis, DFT study and molecular docking inspection of 4,5-bis (2-chlorophenyl)-8a-phenylhexahydropyrimido[4,5-d]pyrimidine-2,7 (1H,3H)-dithione
    (Elsevier, 2025) Ahsin, Atazaz; Kurbanova, Malahat; Ahmad, Sajjad; Qamar, Aamna; Ashfaq, Muhammad; Tahir, Muhammad Nawaz; Dege, Necmi
    We studied the three-component condensation of 2-chloraldehyde, acetophenone, and thiourea in conjunction with HCl, resulting in the formation of a new compound: 4,5-bis(2-chlorophenyl)-8a-phenylhexahydropyrimido [4,5-d]pyrimidine-2,7(1H,3H)-dithione (CPPD). The compound's structure was affirmed via X-ray diffraction study. The asymmetric unit contained two molecules that were independent relative to crystallography and an ethanol solvent. The difference between independent molecules was explored by dihedral angles between similar rings in both molecular. The difference between molecules was further explored by molecular overlay plot. The supramolecular assembly was supported via diverse intermolecular interactions which were studied through the use of Hirshfeld surface analysis. Electronic structure computations were carried out at the omega b97xd/tzvp level. Natural bonding orbital (NBO), and FMO study reveal reactivity and charge transfer mechanisms within the compound. Furthermore, the nature of bonding in the present molecule is characterized through quantum theory of atoms in molecules (QTAIM), ELF, and LOL studies. Ab-initio molecular dynamic (AIMD) revealed the kinetic and thermodynamic stability at 300 K. The DFT results have excellent correlation with experimental data. The molecular docking and molecular dynamics simulation further revealed the compound to get deep access in the active pocket of type 2 anti-diabetes GLUT4 protein. This was validated by the stable dynamics as demonstrated by the uniform behavior of the root mean square deviation (RMSD) plot. The root mean square fluctuation (RMSF) also showed stable interactions with amino acids in the presence of the compound. Further, simulation trajectories on the basis of binding free energies indicate the significant role of van der Waals force in the formation of the intermolecular docked complex. This concluded the compound might be a potent structure for the development of anti-diabetic compounds.