DFT, Molecular Docking, Bioactivity and ADME Analyses of Vic-dioxim Ligand Containing Hydrazone Group and its Zn(II) Complex

BACKGROUND

Cancer is one of the diseases affecting a large population worldwide and resulting in death. Finding new anti-cancer drugs that are target-focused and have low toxicity is of great importance.

OBJECTIVE

This study aimed to investigate the effects of vic-dioxime derivatives carrying hydrazone group and its Zn(II) complex on cancer using molecular docking, bioactivity and quantum chemical calculations.

METHODS

Molecular docking studies were performed on epidermal growth factor receptor and vascular endothelial growth factor receptor 2 target proteins. Furthermore, molecular geometry was performed, and the frontier molecular orbitals, Mulliken charges and molecular electron density distribution were evaluated using density functional theory. Also, the bioactivity parameters of the compounds were evaluated, and ADME analysis was performed using web-based tools.

RESULTS

Higher binding affinity was observed for Zn(II) complex with target proteins vascular endothelial growth factor receptor 2 and against epidermal growth factor receptor when compared with LH2. Only the Zn(II) complex against the epidermal growth factor receptor had ligand efficiency and fit quality in the valid range. Furthermore, LH2 has the most potent electrophilic ability (acceptor) among other compounds. Moreover, both LH2 and Zn(II) complexes strongly satisfy Lipinski's rule of five.

CONCLUSION

In conclusion, these novel compounds, especially Zn(II) complex, can be new candidates for anticancer drug development studies which are target-focused and have low toxicity.

Crystal structure of 2-hy-droxy-2-phenyl-aceto-phenone oxime

The title compound [systematic name: 2-(N-hy-droxy-imino)-1,2-di-phenyl-ethanol], C14H13NO2, consists of hy-droxy phenyl-aceto-phenone and oxime units, in which the phenyl rings are oriented at a dihedral angle of 80.54 (7)°. In the crystal, inter-molecular O-HOxm⋯NOxm, O-HHydr⋯OHydr, O-H'Hydr⋯OHydr and O-HOxm⋯OHydr hydrogen bonds link the mol-ecules into infinite chains along the c-axis direction. π-π contacts between inversion-related of the phenyl ring adjacent to the oxime group have a centroid-centroid separation of 3.904 (3) Å and a weak C-H⋯π(ring) inter-action is also observed. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (58.4%) and H⋯C/C⋯H (26.4%) contacts. Hydrogen bonding and van der Waals contacts are the dominant inter-actions in the crystal packing.

Ligands Containing of a C=O and an –Nh–R Adjacent to the Oxime Group and their Cobalt(Ii), Nickel(Ii) and Copper(Ii) Complexes

Ligands having a C=O group and an –NH–R group adjacent to the oxime group have been prepared from ω-chloroisonitrosoacetophenone and aniline or aniline derivatives in the presence of NaHCO3. The Ni(II), Cu(II) and Co(II) complexes of the synthesised ligands have been prepared and characterised. The ligands are proposed to coordinate to the metal ions via the oxime oxygen and amide nitrogen atoms. Thermal analyses data reveals that the water in the complexes is non-coordinated to the metal ions. Binuclear and polymeric structures are suggested for all complexes. The complexes showed an antiferromagnetic effect.

Coordination of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) with 2,5-hexanedione bis(thiosemicarbazone), HBTS: crystal structure of cis-[Pd(HBTS)]Cl2 and 1-(2,5-dimethyl-1H-pyrrol-yl)-thiourea

Metal complexes of Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pd2+ or Pt2+ with 2,5-hexanedione bis(thiosemicarbazone), HBTS; have been prepared and spectroscopically investigated. The empirical formulae of the complexes were suggested based on the elemental analysis. Single crystal of Pd(II) has been solved to be cis-form of square-planar geometry by the X-ray crystallography. 1H and 13C NMR spectra have been recorded for HBTS, Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) complexes, in DMSO-d6, showing the mode of chelation. The ligand acts as a neutral or a binegative tetradentate (N2S2) or neutral bidentate on the basis of FT-IR. The magnetic moments and electronic spectra provide information about the geometry of the complexes which supported by calculating the ligand field parameters for the Co(II) and Fe(III) complexes. The Ni(II) complex has subnormal magnetic moment (0.71 BM) indicative of a mixed stereochemistry of square-planar and tetrahedral structure. [Cu(HBTS-2H)] measured 0.93 BM indicating high interaction between the copper centers. The ligand may be ordered at the top of the spectrochemical series which giving high ligand field splitting energy (10 Dq=17,900 cm(-1) for Co2+ complex). The mass spectra of some complexes proved their stable chemical formulae while the TGA depicts the degradation steps and the final residue. In evaporating the mother liquor during the preparation of HBTS, new compound is obtained naming 1-(2,5-dimethyl-1H-pyrrol-yl)thiourea and its crystal was solved.

Synthesis and spectral characterization of Schiff base complexes of Cu(II), Co(II), Zn(II) and VO(IV) containing 4-(4-aminophenyl)morpholine derivatives: antimicrobial evaluation and anticancer studies

Metal(II) chelates of Schiff bases derived from the condensation of 4-morpholinoaniline with substituted salicylaldehyde have been prepared and characterized by (1)H NMR, IR, electronic, EPR, and magnetic measurement studies. The complexes are of the type M(X-MPMP)2 [where M=Cu(II), Co(II)), Zn(II), or VO(IV); MPMP=2-[(4 morpholinophenyl imino) methyl] 4-X-phenol, X=Cl, (L1H), X=Br (L2H)]. Single crystal X-ray crystallography studies confirm the structure of newly synthesized Schiff bases. The Schiff bases act as bidentate monobasic ligands, coordinating through deprotonated phenolic oxygen and azomethine nitrogen atoms. The free ligands and metal complexes are screened for their biopotency. Metal complexes exhibit better activity than ligands. Anticancer activity of ligands and their metal complexes are evaluated in human heptocarcinoma(HepG2) cells. The preliminary bioassay indicates that the Schiff base and its zinc complex exhibit inhibitory activity against the human gastric cancer cell lines.

Metal based new triazoles: their synthesis, characterization and antibacterial/antifungal activities

A series of new triazoles and their oxovanadium(IV) complexes have been synthesized, characterized and evaluated for antibacterial/antifungal properties. The new Schiff bases ligands (L(1))-(L(5)) were prepared by the condensation reaction of 3,5-diamino-1,2,4-triazole with 2-hydroxy-1-naphthaldehyde, pyrrole-2-carboxaldehyde, pyridine-2-carboxaldehyde, 2-acetyl pyridine and 2-methoxy benzaldehyde. The structures of the ligands have been established on the basis of their physical, spectral (IR, (1)H and (13)C NMR and mass spectrometry) and elemental analytical data. The prepared ligands were used to synthesize their oxovanadium(IV) complexes (1)-(5) which were also characterized by their physical, spectral and analytical data and proposed to have a square pyramidal geometry. The ligands and their complexes were screened for in vitro antibacterial activity against six bacterial species such as, Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus, and Bacillus subtilis and for in vitro antifungal activity against six fungal strains, Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani, and Candida glabrata. Cytotoxic nature of the compounds was also reported using brine shrimp bioassay method against Artemia salina.

Screening and evaluation of antioxidant activity of some amido-carbonyl oxime derivatives and their radical scavenging activities

The antioxidant activity of some amido-carbonyl oximes containing a C=O and -NH-R adjacent to the oxime group, [Phenyl-C(=O)-C(=N-OH)-N(-H)-Phenyl(-R)] where R= H, 4-chloro, 4-methyl, 4-methoxy, 3,4-dichloro, 3,4-dimethyl, 3-chloro-4-dimethyl, 3-chloro-4-methoxy, naphthyl and an amido-carbonyl dioxime were investigated in vitro by ferric thiocyanate, total reducing power by potassium ferricyanide reduction, 1,1-diphenyl-2- picryl-hydrazyl (DPPH(.)) free radical scavenging, ferrous ions chelating, superoxide anion radical scavenging and hydrogen peroxide scavenging activity assays. The results indicated that the amido-carbonyl oximes have powerful antioxidant capacity.

2-Hydroxy-imino-1-phenyl-ethanone thio-semicarbazone monohydrate

In the title thio-semicarbazone derivative, C(9)H(10)N(4)OS·H(2)O, intra-molecular N-H⋯N hydrogen bonds result in the formation of two nearly coplanar five- and six-membered rings, which are also almost coplanar with the adjacent phenyl ring. The oxime group has an E configuration and is involved in inter-molecular O-H⋯O hydrogen bonding as a donor. In the crystal structure, intra-molecular O-H⋯S and N-H⋯N and inter-molecular O-H⋯O and N-H⋯S hydrogen bonds generate edge-fused R(2) (2)(8) and R(4) (1)(11) ring motifs. The hydrogen-bonded motifs are linked to each other to form a three-dimensional supra-molecular network.

New Dihydro OO'Bis(Salicylidene) 2,2' Aminobenzothiazolyl Borate Complexes: Kinetic and Voltammetric Studies of Dimethyltin Copper Complex with Guanine, Adenine, and Calf Thymus DNA

The newly synthesized ligand, dihydro OO′bis(salicylidene) 2,2′ aminobenzothiazolyl borate (2), was derived from the reaction of Schiff base of 2-aminobenzothiazole and salicylaldehyde with KBH₄. Cu^II (3) and Zn^II (4) complexes of (2) were synthesized and further metallated with dimethyltindichloride to yield heterobimetallic complexes (5) and (6). All complexes have been thoroughly characterized by elemental analysis, and IR, NMR, EPR, and UV-Vis spectroscopy and conductance measurements. The spectroscopic data support square planar environment around the Cu^II atom, while the Sn^IV atom acquires pentacoordinate geometry. The interaction of complex (5) with guanine, adenine, and calf thymus DNA was studied by spectrophotometric, electrochemical, and kinetic methods. The absorption spectra of complex (5) exhibit a remarkable “hyperchromic effect” in the presence of guanine and calf thymus DNA. Indicative of strong binding of the complex to calf thymus DNA preferentially binds through N₇ position of guanine base, while the adenine shows binding to a lesser extent. The kinetic data were obtained from the rate constants, k_obs, values under pseudo-first-order conditions. Cyclic voltammetry was employed to study the interaction of complex (5) with guanine, adenine, and calf thymus DNA. The CV of complex (5) in the absence and in the presence of guanine and calf thymus DNA altered drastically, with a positive shift in formal peak potential E_pa and E_pc values and a significant increase in peak current. The positive shift in formal potentials with increase in peak current favours strong interaction of complex (5) with calf thymus DNA. The net shift in E_1/2 has been used to estimate the ratio of equilibrium constants for the binding of Cu(II) and Cu(I) complexes to calf thymus DNA.