Investigation of indirubin derivatives: a combination of 3D-QSAR,molecular docking,and ADMET towards the design of new DRAK2 inhibitors

Kinase-related apoptosis-inducing kinase 2 (DRAK2) is a serine/threonine kinase and belongs to the death-associated protein kinase DPAK family, which is responsible for induction of apoptosis in many cell types. Thus, DRAK2 is regarded as a promising target for treatment of autoimmune diseases. To investigate the binding between DRAK2 and indirubin inhibitors and design potent inhibitors, a three-dimensional quantitative structure-activity relationship (3D-QSAR) and molecular docking were performed. Comparative Molecular Similarity Indices Analysis (CoMSIA) was developed using 33 molecules having pIC₅₀ ranging from 8.523 to 5.000 (IC₅₀ in nM). The best CoMSIA model gave a significant coefficient of determination (R²?=?0.93), as well as a (leave-one-out cross-validation coefficient Q² of 0.81. The predictive ability of this model was evaluated by external validation using a test set of eight compounds and yielded a predicted coefficient of determination R²_test of 0.94. The contour maps could provide structural features to improve inhibitory activity. Good consistency between contour maps and molecular docking strongly suggests that the molecular modeling is reliable. Based on these satisfactory results, we designed several new DRAK2 inhibitors and their inhibitory activities were predicted using different models, which are developed on different training and test sets. Additionally, these newly designed inhibitors showed promising results in the preliminary in silico ADMET evaluations compared to the best inhibitor from the studied dataset. This study could be useful in lead identification and optimization for early drug discovery of DRAK2 inhibitors.     

Combining ligand-based and structure-based drug design approaches to study the structure-activity relationships of a β-carboline derivative series

In this study, we investigated the structure-activity relationships of a series of β-carboline alkaloid derivatives using the 2D-QSAR and molecular docking, in order to identify the mode of interaction between β-carboline derivatives and the PLK1 kinase, and determine their key substituents responsible for the cytotoxic activity. The obtained QSAR models using multiple linear regression (MLR) and partial least squares (PLS) methods showed a high correlation between the experimental activity and the predicted one by PLS (R²_PLS?=?0.82, q²?=?0.72) and MLR (R²_MLR?=?0.82, q²?=?0.72). An external dataset was used to test the extrapolation power of the models which resulted in an R²_PLS (EV)?=?0.76; RMSE?=?0.39. The 2D-QSAR analysis reveals that lipophilicity plays an important role in the cytotoxic activity of this group of β-carboline derivatives. Indeed, the molecular docking study into the active site of the polo-like kinase (PLK1) revealed that the most active ligand 57 shows higher binding energy and interacts, especially by H-bonds and hydrophobic interactions, with the active site of the PLK1 kinase. Consequently, the results obtained from the 2D-QSAR and docking studies provided a useful tool to design new and potent β-carboline derivatives as cytotoxic agents.     

Discovery of novel inhibitors for <Emphasis Type="Italic">Leishmania</Emphasis> nucleoside diphosphatase kinase (NDK) based on its structural and functional characterization

Nucleoside diphosphate kinases (NDKs) are ubiquitous enzymes that catalyze the transfer of the γ-phosphate moiety from an NTP donor to an NDP acceptor, crucial for maintaining the cellular level of nucleoside triphosphates (NTPs). The inability of trypanosomatids to synthesize purines de novo and their dependence on the salvage pathway makes NDK an attractive target to develop drugs for the diseases they cause. Here we report the discovery of novel inhibitors for Leishmania NDK based on the structural and functional characterization of purified recombinant NDK from Leishmania amazonensis. Recombinant LaNDK possesses auto-phosphorylation, phosphotransferase and kinase activities with Histidine 117 playing an essential role. LaNDK crystals were grown by hanging drop vapour diffusion method in a solution containing 18% PEG-MME 500, 100 mM Bis-Tris propane pH 6.0 and 50 mM MgCl₂. It belongs to the hexagonal space group P6₃22 with unit cell parameters a?=?b?=?115.18, c?=?62.18 Å and α?=?β?=?90°, γ?=?120°. The structure solved by molecular replacement methods was refined to crystallographic R-factor and R_free values of 22.54 and 26.52%, respectively. Molecular docking and dynamics simulation-based virtual screening identified putative binding compounds. Protein inhibition studies of selected hits identified five inhibitors effective at micromolar concentrations. One of the compounds showed ~45% inhibition of Leishmania promastigotes proliferation. Analysis of inhibitor-NDK complexes reveals the mode of their binding, facilitating design of new compounds for optimization of activities as drugs against leishmaniasis.     

Identification of molecular fingerprints of phenylindole derivatives as cytotoxic agents: a multi-QSAR approach

Phenylindole is reported to be an interesting scaffold having promising cytotoxic activities and can overcome the cancer drug resistance possibly via binding to the colchicine binding site of tubulin. In order to find out the molecular fingerprints for the better cytotoxic activity of phenylindole derivatives, multiple validated chemometric modeling approaches namely hologram QSAR (HQSAR), Bayesian classification model, and pharmacophore mapping analyses were applied into a dataset of 102 phenylindole derivatives. The final HQSAR model shows good statistical significance (Q²?=?0.760; R²_Train?=?0.868; R²_Test?=?0.660), and the best pharmacophore hypothesis has the highest regression coefficient value (r?=?0.975) and the lowest RMS value of 0.679. Moreover, the Bayesian model is also statistically validated and robust to discriminate the cytotoxic and non-cytotoxic phenylindoles. These studies suggest that the amine group should be unsubstituted for retaining higher cytotoxicity. The pharmacophore mapping and Bayesian classification study suggest the importance of 2-phenyl group as a ring aromatic feature conducive to cytotoxicity. The steric and hydrophobic effect of long chain linear alkyl group has a positive influence on cytotoxicity as evidenced by the multi-QSAR study. Therefore, this multi-QSAR modeling reported here is beneficial in designing potential phenylindole cytotoxic agents in future.     

Structural basis of pyrazolopyrimidine derivatives as CAMKIIδ kinase inhibitors: insights from 3D QSAR,docking studies and in silico ADMET evaluation

Ca²⁺/calmodulin-dependent protein kinase II (CAMKIIδ) belongs to the serine/threonine kinase family, which is involved in a broad range of cellular events in cell survival and proliferation as well as a number of other signal transduction pathways. Thus, it is regarded a promising target for treatment of cancers. In the present paper, a three-dimensional quantitative structure–activity relationship and molecular docking were applied to investigate a series of new CAMKIIδ inhibitors of pyrazolopyrimidine derivatives. The determination coefficient (R²) and leave-one-out cross-validation coefficient (Q²) of CoMSIA model are 0.676 and 0.956, respectively. The predictive ability of this model was evaluated by the external validation using a test set of eight compounds with a predicted determination coefficient \(R^{ 2}_{\text{test}}\) of 0.80, besides the mean absolute error of the test set was 0.328 log units. Docking results are in concordance with CoMSIA contour maps, gave the information for interactive mode exploration. Based on those satisfactory results, newly designed molecules were predicted with highly potent CAMKIIδ inhibitory activity, additionally, they have showed promising results in the preliminary in silico ADMET evaluations. This study could expand our understanding of pyrazolopyrimidine derivatives as inhibitors of CAMKIIδ and would be of great help in lead optimization for early drug discovery of highly potent CAMKIIδ inhibitors.     

3D QSAR Studies on Benzyl Phenyl Ether Diamidine Derivatives with Antiprotozoal Activities

Human African trypanosomiasis (HAT) is a neglected tropical disease, and some drugs treating HAT have been used for even more than 60 years. Currently, a series of benzyl phenyl ether diamidine derivatives are discovered, which exhibit high antiprotozoal activities and low cytotoxicity, leading to good development prospects. The comparative molecular field analysis (CoMFA) and the comparative molecular similarity indices analysis (CoMSIA) are used to study the relationship between the structure and antiprotozoal activities. The established 3D QSAR model shows not only significant statistical quality, but also satisfies predictive ability: the best CoMFA model had r² = 0.958 and q² = 0.766, the best CoMSIA model had r² = 0.957 and q² = 0.812, the predictive ability of CoMFA and CoMSIA model were further confirmed by a test set which had 11 compounds, giving the correlation coefficient Q_ext² of 0.792, 0.873, respectively. The contour maps and contribution maps show important features that can improve the antiprotozoal activity: position 3 from substituent R4 should be a low electronegativity group, position 4 from substituent R₄ should have higher electronegativity, substituent R₂ should be selected to a low electronegativity and small bulk group. Together these results may offer some useful theoretical information in designing potential inhibitors.     

2-amino-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyrimidines: Synthesis and reactions with electrophilic reagents

The hydrogenation of 2-amino-5-R-7-R′-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidines with NaBH₄ led to the formation of 2-amino-5-R-7-R′-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]pyrimidines. Acylation, sulfonylation, and alkylation of these compounds depending on conditions and the reagent character occur at the amino group, atoms N³ or N⁴. The treatment with alkali of 2-amino-3-benzyl-5-R-7-R′-4,5,6,7-tetrahydro-1,2,4-triazolo-[1,5-a]pyrimidinium bromide resulted in 2-amino-3-benzyl-5-R-7-R′-3,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]-pyrimidine, similar reaction of 2-acetamido-3-benzyl-5-R-7-R′-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]-pyrimidinium bromide gave a mesoionic product of a hydrogen elimination from the amide nitrogen atom.     

Pharmacophore interactions analysis and prediction of inhibitory activity of 1,7-diazacarbazoles as checkpoint kinase 1 inhibitors: application of molecular docking, 3D-QSAR and RBF neural network

In the present study, we mainly focused on new synthesized 1,7-diazacarbazole derivatives (44 active molecules) as Chk1 inhibitors to build 3D-QSAR model. Comparative molecular field analysis (CoMFA) model with three principal components was developed. The relative contributions in building of CoMFA model were 64.41 % for steric field and 35.59 % for electrostatic field. R ² values for training and test sets of CoMFA model were 0.8724 and 0.7818, respectively, and squared correlation coefficient for leave-one-out cross-validation test (q ²) was 0.6753. To improve the predictive power, a new 3D-QSAR model was developed by using radial basis function network (RBFN) and score of CoMFA interactions energy values as input variables. Scores 1, 2 and 3 were used as input variables, and a RBFN model with seven centers and spread value equal to 95 was developed to create a nonlinear 3D-QSAR model. R ² values for training and test sets were 0.9613 and 0.8564, and q ² for leave-one-out cross-validation test was 0.9258. Docking of all molecules to 3DX ligand binding site of Chk1 receptor indicated six interactions as pharmacological interactions between compounds and binding site of receptors. These pharmacological interactions were hydrogen bonding with LEU-15 and GLU-85 in main chain and four van der Waals interactions with LEU-15, VAL-23, TYR-86 and LEU-137 in side chain. CoMFA contour plots were used to design new inhibitors, and inhibitory activity of each compound was predicted by using CoMFA and RBFN models.     

Computational explorations to gain insight into the structural features of TNF-α receptor I inhibitors

TNF-α is a crucial cytokine in the process of inflammatory diseases. The adverse effect of TNF-α is mostly mediated by interaction of TNF-α with TNF-α receptor type I (TNFR1); therefore, discovery of molecules which can bind to TNFR1 preventing TNF-α-receptor complex formation would be of great interest. In the current study, using GRID/GOLPE program, a 3D-QSAR study was conducted on a series of synthetic TNFR1 binders, which resulted in a 3D-QSAR model with appropriate power of predictivity in internal (r²?=?0.94 and q²_LOO?=?0.74) and external (r²?=?0.66 and SDEP?=?0.42) validations. The structural features of TNFR1 inhibitors essential for exerting activity were explored by analyzing the contour maps of the 3D-QSAR model showing that steric interactions and hydrogen bonds are responsible for exerting TNFR1 inhibitory activity. To propose potential chemical entities for TNFR1 inhibition, PubChem database was searched and the selected compounds were virtually tested for anti-TNFR1 activity using the generated model, resulting in two potential anti-TNFR1 compounds. Finally, the possible interactions of the compounds with TNFR1 were investigated using docking studies. The findings in the current work can pave the way for designing more potent anti-TNFR1 inhibitors.     

Synthesis,crystal structure,and kinetics of thermal decomposition of the Zn(II) complex with vanillin

A complex [Zn(C₈H₇O₃)₂(H₂O)₂] (C₈H₈O₃ is vanillin) has been synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. The crystals are monoclinic, space group C2/c, a = 22.236(8) Å, b = 10.594(2) Å, c = 7.8190(16) Å, α = 89.90(3)°, β = 106.87(4)°, γ = 89.99(3)°, V = 1762.6(8) ų, Z = 4, F(000) = 832, S = 1.079, ρ _c = 1.521g cm^?3, R = 0.0221, R _w = 0.0604, μ = 1.433 mm^?1. The Zn²⁺ ion is six-coordinated with a distorted octahedron geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds. The thermal decomposition kinetics of the complex for the second stage was studied under non-isothermal conditions by the TG and DTG methods. The kinetic equation can be expressed as dα/dt = Ae^?E/RT 2(1 ? α)[1 ? ln(1 ? α)]^1/2. The kinetic parameters (E, A), activation entropy ΔS ^≠, and activation free-energy ΔG ^≠ were also gained.     

Structure elucidation and X-ray crystallographic study of 3-(naphth-1-ylmethyl)indole

Synthesis and structure determination of 3-(naphth-1-ylmethyl)indole are reported. The molecular and crystal structures together with the molecular formula were determined by spectral and single crystal X-ray studies. X-ray crystallography revealed the presence of two conformers arising from the flipping of the naphthalene unit. The crystal of the compound belongs to the triclinic crystal system and space group \(P\bar 1\). Crystal data are as follows: a = 10.302(5) Å, b = 12.522(4) Å, c = 13.383(4) Å, α = 111.9(1)°, β = 116.86(6)°, γ = 71.65(5)°; V = 1726.429 ų; Z = 4. The final R and Rw are R = 0.0744 (on observed F′s); R = 0.0924 (all F data), R _w = 0.1757 (observed F ²) and R _w = 0.1834 (all F ² data).     

Crystal structure of Iron(III) hydrogen diphosphate FeHP<Subscript>2</Subscript>O<Subscript>7</Subscript>

The crystal structure of the β modification of iron(III) hydrogen diphosphate FeHP₂O₇ has been refined by the Rietveld method using powder X-ray diffraction data. The compound crystallizes in the monoclinic system, space group P2₁/n, Z = 4, a = 7.9756(1) Å, b = 12.8260(2) Å, c = 4.8664(6) Å, β = 98.6404(8)°, V = 492.16(1) ų. The structure was refined in the isotropic approximation (pseudo-Voigt function), R _p = 0.024, R _wp = 0.033, R _Bragg = 0.091, R _F = 0.067, and compared with the structures of other compounds M^IIIHP₂O₇ (M^III is a trivalent metal).     

Theoretical and experimental study of molecular structure and vibrational spectra of <Emphasis Type="Italic">N</Emphasis>-(2-pyridylmethyl)-2-pyrazinecarboxamide

N-(2-Pyridylmethyl)-2-pyrazinecarboxamide was prepared and its crystal structure was investigated by X-ray analysis. The compound crystallizes in the triclinic space group \(P{\bar 1}\) with a = 4.262(3), b = 12.117(9), c = 20.840(18) Å, α = 91.802(6), β = 89.834(7), γ = 91.845(6)°, V = 1075.2(16) ų, Z = 4, and D = 1.323?Mg/m³. The structure was solved by direct method and refined to R = 0.0699 and wR ₂ = 0.1268 by full matrix anisotropic least-squares method. Using the Hartree-Fock and density functional method (B3LYP) with 6-31G(d) basis set, the molecular geometry and vibrational frequencies of the title compound has been investigated and compared with experimental ones from experimental studies. The optimized bond lengths obtained by RHF method and bond angles obtained by B3LYP method show better agreement with the experimental values. The vibrations computed of the title compound by the RHF and DFT methods are in good agreement with the observed IR spectra data.     

Crystal and Molecular Structure of (4′<Emphasis Type="Italic">R</Emphasis>,5′<Emphasis Type="Italic">R</Emphasis>,22<Emphasis Type="Italic">R</Emphasis>)-22-Hydroxy-22-(3′,4′-dimethylisoxazolin-5′-yl)-6β-methoxy-3α,5-cyclo-23,24-dinorcholane

The crystal and molecular structure of (4′R,5′R,22R)-22-hydroxy-22-(3′, 4′-dimethylisoxazolin-5′-yl)-6β-methoxy-3α,5-cyclo-23,24-dinorcholane was studied by single crystal X-ray diffraction. The compound crystallizes in the monoclinic system, space group C2; a 19.649(7), b 7.680(2), c 17.254(6) Å; β 101.05(3)°. The only diastereomer formed by the 1,3-dipolar cycloaddition of acetonitriole oxide has the 4′R,5′R stereochemistry of the arising chiral centers. The conformation of the side chain of the molecule is additionally stabilized by an intramolecular hydrogen bond.     

Synthesis,Structures, and Antibacterial Activities of Two Methanol Coordinated Zinc Complexes with Tetradentate Bis-Schiff Bases

Two methanol coordinated zinc(II) complexes, [Zn(L¹)(MeOH)] (I) and [Zn(L²)(MeOH)] (II), where L¹ and L² are the dianionic form of N,N'-bis(5-fluorosalicylidene)ethane-1,2-diamine and N,N'-bis(5-fluorosalicylidene)propane-1,2-diamine, respectively, have been synthesized and characterized by physical chemical methods and single crystal X-ray diffraction (CIF files CCDC nos. 950907 (I) and 950908 (II)). Crystallographic data for I: triclinic, P \(\bar 1\), a = 8.8765(8), b = 9.6577(9), c = 10.5117(9) Å, α = 114.590(2)°, β = 91.648(3)°, γ = 97.114(3)°, V = 809.87(13) ų, Z = 2, R ₁ = 0.0307, wR ₂ = 0.0698. Crystallographic data for II: orthorhombic, Pca2₁, a = 22.946(2), b = 7.6942(7), c = 9.6234(8) Å, V = 1699.0(2) ų, Z = 4, R ₁ = 0.0320, wR ₂ = 0.0676. X-ray crystal structural study indicated that the coordination environment around each zinc(II) atom in the complexes is a five-coordinated distorted pyramid in which the apical position is occupied by a methanol oxygen atom, and the basal plane is defined by the nitrogen and oxygen donor atoms of the Schiff base ligand. The antibacterial activities of the complexes were assayed.     

Synthesis,characterization, and crystal structures of dioxomolybdenum(VI) complexes with O,N,N type tridentate hydrazone ligands as catalyst for oxidation of olefins

The preparation of Mo(VI) hydrazone complexes, cis-[MoO₂L¹(CH₃OH)] (I) and cis-[MoO₂L₂(CH₃OH)] (II), derived from N'-(3-bromo-2-hydroxybenzylidene)-2-chlorobenzohydrazide (H₂L¹) and N'-(3-bromo-2-hydroxybenzylidene)-4-bromobenzohydrazide (H₂L²), respectively, is reported. The complexes were characterized by elemental analyses, infrared and electronic spectroscopy, and single crystal structure analysis (CIF files ССDС nos. 1426875 (I), 1426871 (II)). The Mo atoms are coordinated by two cis terminal oxygen, ONO from the hydrazone ligand, and methanol oxygen. Even though the hydrazone ligands and the coordination sphere in both complexes are similar, the unit cell dimensions and the space groups are different. Complex I crystallized as orthorhombic space group Pca21 with unit cell dimensions a = 27.887(2), b = 8.0137(7), c = 15.544(1) Å, V = 3473.8(5) ų, Z = 8, R ₁ = 0.0450, wR ₂ = 0.0539. Complex II crystallized as triclinic space group P1, with unit cell dimensions a = 8.2124(4), b = 8.5807(5), c = 12.9845(8) Å, α = 83.366(2)°, β = 79.201(2)°, γ = 80.482(2)°, V = 883.03(9) Å3, Z = 2, R ₁ = 0.0278, wR ₂ = 0.0569. The complexes were tested as catalyst for the oxidation of olefins, and showed effective activity.     

Crystal structure and properties of [M(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl](NO<Subscript>3</Subscript>)<Subscript>2</Subscript>, (M = Ir,Rh, Ru)

The crystal structures of compounds from the series [M(NH₃)₅Cl](NO₃)₂, (M = Ir, Rh, Ru) were described. The compounds crystallized in the tetragonal crystal system, space group I4, Z = 2. Crystal data for [Ir(NH₃)₅Cl](NO₃)₂ (I): a = 7.6061(1) Å, b = 7.6061(1) Å, c = 10.4039(2) Å, V = 601.894(16) ų, ρ_calc = 2.410 g/cm³, R = 0.0087; [Rh(NH₃)₅Cl](NO₃)₂ (II): a = 7.5858(5) Å, b = 7.5858(5) Å, c = 10.41357(7) Å, V = 599.24(7) ų, ρ_calc = 1.926 g/cm³, R = 0.0255; [Ru(NH₃)₅Cl](NO₃)₂ (III): a = 7.5811(6) Å, b = 7.5811(6) Å, c = 10.5352(14) Å, V = 605.49(11) ų, ρ_calc = 1.896 g/cm³, R = 0.0266. The compounds were defined by IR spectroscopy and XRPA and thermal analyses.     

Reaction of 3-oxo-3-R<Superscript>1</Superscript>-<Emphasis Type="Italic">N</Emphasis>-R<Superscript>2</Superscript>-propanethioamides with 2-amino-5-R-pyridines

Direction of a reaction between 3-oxo-3-R¹-N-R²-propanethioamides and 2-amino-5-R-pyridines in acetic acid depends on the structure of initial thioamides: at R¹ = Me, R² = Ar, Et 2-methyl-7-R-4H-pyrido[1,2-a]-pyrimidine-4-thiones are obtained, and at R¹ = Ar, R² = Me form 1-methyl-5-(N-methylaminothiocarbonyl)-4,6-diaryl-1,2-dihydropyridine-2-thiones.     

Synthesis and crystal structure of a new Schiff base ligand and its cobalt(II) complex

The crystal structures of cobalt(II) Schiff base complex (Co^IIL₂ · H₂O) and Schiff base ligand 3,5-dichlorosalicylidene-2-chlorophenylmethylamine (HL) have been determined by single-crystal X-ray analysis. The geometry around cobalt in Co^IIL₂ · H₂O is distorted tetrahedral. Co^IIL₂ · H₂O crystallizes in the monoclinic system, in space group C2/c, with crystallographic parameters: a = 12.9143(16) Å, b = 8.8326(16) Å, c = 25.115(3) Å, β = 92.791(10)°, V = 2861.4(7) ų, Z = 4, F(000) = 1420, and the final R indices (I > 2σ(I)) are R ₁ = 0.0440, wR ₂ = 0.1272. HL crystallizes in the monoclinic system, in space group P2₁/c, with crystallographic parameters: a = 11.9764(15), b = 8.2331(10), c = 14.2211(17) Å, β = 98.723(6)°, V = 1386.0(3) ų, Z = 4, F(000) = 640, and the final R indices (I > 2σ(I)) are R ₁ = 0.0397, wR ₂ = 0.1018.     

Crystal structure determination,and DFT Calculations of dichlorobis-(dimethylsulfoxide-O)copper(II)

The crystal structure of dichlorobis(dimethylsulfoxide-O)copper(II), [CuCl₂(DMSO)₂] (I), previously determined by Willett and Chang, is reinvestigated. It crystallizes in the orthorhombic system with the space group Pnma (N°62), Z = 4, and unit cell parameters a = 8.053(1) Å, b = 11.642(5) Å, c = 11.347(3) Å. Our structure determination is of a significantly higher precision in terms of bond lengths, angles, and R factors (e.g., Cu1–O1 = 1.9737(24) Å, O1–Cu1–O1ⁱ = 173.08(13)° (symmetry code: ^I x, 1/2–y, z) and R(F ²) = 0.046 compared to 1.955(4) Å, 173.0(3)° and R(F) = 0.075). In contrast to the previous investigation, all H atoms are placed at calculated positions. In the title molecule, the Cu^II atom is five coordinated in a distorted square pyramidal geometry. Thus, as reported previously, it can be shown that the crystal structure consists of [CuCl₂(DMSO)₂] molecules which, by virtue of long Cu–Cl interactions, are tied together to form chains parallel to the [100] direction. The density functional theory (DFT) optimized structure at the B3LYP/6-311++G(2d,2p) level is compared with the experimentally determined molecular structure. The HOMO-LUMO energy gap and other related molecular properties are also calculated. Comprehensive experimental and theoretical structural studies on the studied complex are carried out by FT-IR and UV-visible spectroscopies.