Synthesis, structure, computational and in-silico anticancer studies of N,N -diethyl- N ′-palmitoylthiourea

Structure and surface analyses of a newly synthesized acyl thiourea derivative along with its in silico and in vitro investigations for RNR, DNA binding, urease inhibition and radical scavenging activities

N-((4-Acetylphenyl)carbamothioyl)-2,4-dichlorobenzamide (4) was synthesized by the treatment of 2,4-dichlorobenzoyl chloride with potassium thiocyanate in a 1 : 1 molar ratio in dry acetone to afford the 2,4-dichlorobenzoyl isothiocyanate in situ which on reaction with acetyl aniline furnished (4) in good yield and high purity. The compound was confirmed by FTIR, 1H-NMR, and 13C-NMR and single crystal X-ray diffraction studies. The planar rings were situated at a dihedral angle of 33.32(6)°. The molecules, forming S(6) ring motifs with the intramolecular N-H⋯O hydrogen bonds, were linked through intermolecular C-H⋯O and N-H⋯S hydrogen bonds, enclosing R2 2(8) ring motifs, into infinite double chains along [101]. C-H⋯π and π⋯π interactions with an inter-centroid distance of 3.694 (1) Å helped to consolidate a three-dimensional architecture. Hirshfeld surface (HS) analysis further indicated that the most important contributions for the crystal packing were from H⋯C/C⋯H (20.9%), H⋯H (20.5%), H⋯Cl/Cl⋯H (19.4%), H⋯O/O⋯H (13.8%) and H⋯S/S⋯H (8.9%) interactions. Thus C-H⋯π (ring), π⋯π, van der Waals interactions and hydrogen bonding played the major roles in the crystal packing. The electronic structure and computed DFT (density functional theory) parameters identified the reactivity profile of compound (4). In silico binding of (4) with RNA indicated the formation of a stable protein-ligand complex via hydrogen bonding, while DNA docking studies inferred (4) as a potent groove binder. The experimentally observed hypochromic change (57.2%) in the UV-visible spectrum of (4) in the presence of varying DNA concentrations together with the evaluated binding parameters (K b; 7.9 × 104 M-1, ΔG; -28.42 kJ mol-1) indicated spontaneous interaction of (4) with DNA via groove binding and hence supported the findings obtained through docking analysis. This compound also showed excellent urease inhibition activity in both in silico and vitro studies with an IC50 value of 0.0389 ± 0.0017 μM. However, the radical scavenging efficiency of (4) was found to be modest in comparison to vitamin C.

Crystal structure, Hirshfeld surface and computational study of 1-(9,10-dioxo-9,10-di-hydroanthracen-1-yl)-3-propano-ylthio-urea

The title compound, C18H14N2O3S, crystallizes in the ortho-rhom-bic crystal system and Pbca space group. The thio-urea chromophore is planar to an r.m.s deviation of 0.032 Å with the thiol-ate sulfur atom being the most deviated. Bifurcated N-H⋯O intra-molecular hydrogen bonds result in an S(6) supra-molecular synthon. In the crystal, mol-ecules are linked by N-H⋯O inter-molecular hydrogen-bonding inter-actions and stabilized by C-H⋯π and π-π inter-actions. Hirshfeld surface analysis and fingerprint plot indicate the H⋯H inter-molecular contacts as the highest contributor to the overall surface contacts (38%) and this is supported by the high dispersive and electrostatic inter-action energies.

Single-Crystal Investigation, Hirshfeld Surface Analysis, and DFT Study of Third-Order NLO Properties of Unsymmetrical Acyl Thiourea Derivatives

In the current research work, unsymmetrical acyl thiourea derivatives, 4-((3-benzoylthioureido)methyl)cyclohexane-1-carboxylic acid (BTCC) and methyl 2-(3-benzoylthioureido)benzoate (MBTB), have been synthesized efficiently. The structures of these crystalline thioureas were unambiguously confirmed by single-crystal diffractional analysis. The crystallographic investigation showed that the molecular configuration of both compounds is stabilized by intramolecular N-H···O bonding. The crystal packing of BTCC is stabilized by strong N-H···O bonding and comparatively weak O-H···S, C-H···O, C-H···π, and C-O···π interactions, whereas strong N-H···O bonding and comparatively weak C-H···O, C-H···S, and C-H···π interactions are responsible for the crystal packing of MBTB. The noncovalent interactions that are responsible for the crystal packing are explored by the Hirshfeld surface analysis for both compounds. The void analysis is performed to find the quantitative strength of crystal packing in both compounds. Additionally, state-of-the-art applied quantum chemical techniques are used to further explore the structure-property relationship in the above-entitled molecules. The optimization of molecular geometries showed a reasonably good correlation with their respective experimental structures. Third-order nonlinear optical (NLO) polarizability calculations were performed to see the advanced functional application of entitled compounds as efficient NLO materials. The average static γ amplitudes are found to be 27.30 × 10^-36 and 102.91 × 10^-36 esu for the compounds BTCC and MBTB, respectively. The γ amplitude of MBTB is calculated to be 3.77 times larger, which is probably due to better charge-transfer characteristics in MBTB. The quantum chemical analysis in the form of 3-D plots was also performed for their frontier molecular orbitals and molecular electrostatic potentials for understanding charge-transfer characteristics. We believe that the current investigation will not only report the new BTCC and MBTB compounds but also evoke the interest of the materials science community in their potential use in NLO applications.

Crystal structure and Hirshfeld surface analysis of a new di-thio-glycoluril: 1,4-bis-(4-meth-oxy-phen-yl)-3a-methyl-tetra-hydro-imidazo[4,5-d]imidazole-2,5(1H,3H)-di-thione

In the title di-thio-glycoluril derivative, C19H20N4O3S2, there is a difference in the torsion angles between the thio-imidazole moiety and the meth-oxy-phenyl groups on either side of the mol-ecule [C-N-Car-Car = 116.9 (2) and -86.1 (3)°, respectively]. The N-C-N bond angle on one side of the di-thio-glycoluril moiety is slightly smaller compared to that on the opposite side, [110.9 (2)° cf. 112.0 (2)°], probably as a result of the steric effect of the methyl group. In the crystal, N-H⋯S hydrogen bonds link adjacent mol-ecules to form chains propagating along the c-axis direction. The chains are linked by C-H⋯S hydrogen bonds, forming layers parallel to the bc plane. The layers are then linked by C-H⋯π inter-actions, leading to the formation of a three-dimensional supra-molecular network. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to investigate the mol-ecular inter-actions in the crystal.

Computational Approaches Towards Kinases as Attractive Targets for Anticancer Drug Discovery and Development

BACKGROUND

One of the major goals of computational chemists is to determine and develop the pathways for anticancer drug discovery and development. In recent past, high performance computing systems elicited the desired results with little or no side effects. The aim of the current review is to evaluate the role of computational chemistry in ascertaining kinases as attractive targets for anticancer drug discovery and development.

METHODS

Research related to computational studies in the field of anticancer drug development is reviewed. Extensive literature on achievements of theorists in this regard has been compiled and presented with special emphasis on kinases being the attractive anticancer drug targets.

RESULTS

Different approaches to facilitate anticancer drug discovery include determination of actual targets, multi-targeted drug discovery, ligand-protein inverse docking, virtual screening of drug like compounds, formation of di-nuclear analogs of drugs, drug specific nano-carrier design, kinetic and trapping studies in drug design, multi-target QSAR (Quantitative Structure Activity Relationship) model, targeted co-delivery of anticancer drug and siRNA, formation of stable inclusion complex, determination of mechanism of drug resistance, and designing drug like libraries for the prediction of drug-like compounds. Protein kinases have gained enough popularity as attractive targets for anticancer drugs. These kinases are responsible for uncontrolled and deregulated differentiation, proliferation, and cell signaling of the malignant cells which result in cancer.

CONCLUSION

Interest in developing drugs through computational methods is a growing trend, which saves equally the cost and time. Kinases are the most popular targets among the other for anticancer drugs which demand attention. 3D-QSAR modelling, molecular docking, and other computational approaches have not only identified the target-inhibitor binding interactions for better anticancer drug discovery but are also designing and predicting new inhibitors, which serve as lead for the synthetic preparation of drugs. In light of computational studies made so far in this field, the current review highlights the importance of kinases as attractive targets for anticancer drug discovery and development.