H2O Complex Research Articles

Theoretical studies on complexes with ammonia: comparison with H2O complexes: hydrogen bonding

High-level theoretical results for structures, dissociation energies and vibrational frequencies of the ammonia complexes NH3–N2, NH3–CO, NH3–O2, NH3–NO, NH3–H2, NH3–F2, NH3–HF, NH3–Ne, NH3–Ar, NH3–CO2, NH3–N2O and NH3–NH3 are reported, and compared with results for corresponding complexes of H2O. While complexes of H2O with N2, CO, NO, Ne, Ar and NH3 are hydrogen bonded, of the complexes with NH3 only NH3-NH3 qualifies. However, for NH3–CO, NH3–N2 and NH3-Ne structures with weak hydrogen bonding are predicted by present theoretical results. Structures of H2, F2, HF, CO2 and N2O complexes with NH3 are similar to those with H2O, not hydrogen bonded, having AB face N of NH3. Their dissociation energies De are close to those of H2O-AB. Due to complex formation, some large changes are noted in vibrational frequencies and infrared intensities, especially for the NH3 dimer and for NH3–HF.

Microsolvation of the Be-F bond in complexes of BeF2, BeF3 –1, and BeF4 –2 with nH2O, for n = 1–6

Ab initio MP2/aug’-cc-pVTZ calculations have been carried out to determine the structures and binding energies of complexes of BeF2, BeF3 –1, and BeF4 –2 with n H2O molecules, with n = 1–6. For each series of complexes with BeF2, BeF3 –1, and BeF4 –2, the binding energies increase as the number of water molecules increases, but the binding energies per intermolecular bond for complexes formed between BeF2 and BeF4 –2 and nH2O decrease as the number of water molecules increases. The binding energies per bond of the BeF3 –1 complexes show little dependence on the number of H2O molecules present. Intermolecular O-H … F hydrogen bonds (HB) stabilise all complexes of H2O with the beryllium bases except for BeF2:1H2O and BeF2:2H2O. Complexes of BeF2 are also stabilised by O … Be beryllium bonds (BeB) and O-H … O hydrogen bonds. EOM-CCSD calculations have also been performed to determine the spin–spin coupling constants. The one-bond coupling constants 1J(Be-F) increase as the Be-F distance decreases, and exhibit an excellent second-order correlation with that distance. 2hJ(O-F) coupling constants across O-H … F hydrogen bonds also exhibit a second-order dependence on distance. Coupling constants 1beJ(O-Be) and 2hJ(O-O) are found in complexes with BeF2 and exhibit a linear dependence on the Be-O and O-O distances, respectively.

An amino-functionalized three-dimensional cadmium metal–organic framework: Synthesis, characterization and excellent fluorescence sensing of Fe3+

An amino-functionalized three-dimensional cadmium metal–organic framework, [Cd1.5(L)(DMF)]·2H2O (complex 1) L = H3TTCA-NH2 = 2′-amino-[1,1′:3′,1″-terphenyl]-4,4″,5′-tricarboxylic acid), is successfully synthesized under solvothermal conditions and structurally characterized. Interestingly, as a transition metal organic framework, the cadmium metal–organic framework exhibits favorable luminescence properties. In addition, the cadmium metal–organic framework reveals excellent selective and sensitive fluorescence sensing for the recognition of Fe3+ with high quenching efficiency ( Ksv = 3.340 × 103 M−1), demonstrating that the cadmium metal–organic framework can be used as a potential sensor for Fe3+.

The orbital picture of the first dipole hyperpolarizability from many-body response theory.

We present an approach for obtaining a molecular orbital picture of the first dipole hyperpolarizability (β) from correlated many-body electronic structure methods. Ab initio calculations of β rely on quadratic response theory, which recasts the sum-over-all-states expression of β into a closed-form expression by calculating a handful of first- and second-order response states; for resonantly enhanced β, damped response theory is used. These response states are then used to construct second-order response reduced one-particle density matrices (1PDMs), which, upon visualization in terms of natural orbitals (NOs), facilitate a rigorous and black-box mapping of the underlying electronic structure with β. We explain the interpretation of different components of the response 1PDMs and the corresponding NOs within both the undamped and damped response theory framework. We illustrate the utility of this new tool by deconstructing β for cis-difluoroethene, para-nitroaniline, and hemibonded OH· + H2O complex, computed within the framework of coupled-cluster singles and doubles response theory, in terms of the underlying response 1PDMs and NOs for a range of frequencies.

Features of the decomposition of cationic nitrosyl iron complexes with N-ethylthiourea and penicillamine ligands in the presence of albumin

In this work, transformations of two cationic dinitrosyl iron complexes (DNICs), namely, mononuclear with N-ethylthiourea ligands [Fe(SC(NH2)(NHC2H5))2(NO)2]+Cl−∙[Fe(SC(NH2)(NHC2H5))Cl(NO)2]0 (complex 1) and binuclear with penicillamine ligands [Fe2(S(C(CH3)2CH(NH3)COOH))2(NO)4]SO4·5H2O (complex 2) have been investigated in an aqueous solution in the presence of bovine serum albumin (BSA) under anaerobic and aerobic conditions. The spectroscopic measurements have shown that the complexes bind to the protein, which leads to their stabilization. The resulting products are much more stable in the absence of oxygen. The fluorescence measurements indicated that complexes 1 and 2 interact with BSA with equilibrium constants K = 4.9∙105 M−1 and 5.3∙105 M−1, respectively. Complex 1 can bind to the surface due to weak intermolecular interactions, resulting in prolonged generation of NO. Also, the decay product of complex 1, both under anaerobic conditions and in the presence of oxygen, is coordinated with Cys34 and His39 in the hydrophobic pocket of albumin, as evidenced by the appearance of a shoulder at 370–410 nm. As a result of these interactions, a high molecular weight albumin-bound complex is formed, which then slowly decomposes in more than 40 h. Complex 2 and its products are adsorbed on the surface of the protein. However, in the presence of oxygen, protein does not significantly affect the NO release rate.

Ultrasonic synthesis, XRD/HSA-interactions, DFT, time-dependence spectrophotometric stability and thermal analysis of the water-bridge {[Cu(phen)2Br]Br·H2O} complex

The monocationic Cu-phen mononuclear complex was assembled under ultrasonic vibration in a high yield, the presence of one water-bridge connecting both inner with outer-sphere bromides in {[Cu(phen)2Br..]..H2O..Br} was confirmed by XRD-crystal measurement. Moreover, the complex was analyzed by CHN-EA, FT-IR, MS, EDX, UV–Vis., and TGA. The XRD-diffraction analyses indicated the formation of distorted square pyramid [CuBr(phen)2]Br·H2O complex geometry, where the uncoordinated H2O behaved as a bridge-molecule connecting outer-sphere Br- anion with inter-sphere one via two short hydrogen bonds. The thermal decomposition behavior via TG/DTG was also recorded. Moreover, to evaluate the complex stability over time in an aqueous medium the time-repentance spectrophotometric method was performed. The [CuBr(phen)2]Br DFT/B3LYP optimized parameters and Hirschfield surface analysis (HSA) computations were matched to the experimental XRD-structural parameters and XRD-packing results respectively in order to evaluate the accuracies of the B3LYP and HSA theory levels on such complexes.

Uranium MOF derivative based on 2,2',2''-[1 4,6-triyltris(thio)]trisacetic acid as sensor for ruthenium(III) and biomolecules

Two MOFs of uranium derivatives (NH4)[UO2(TTTA)]·2H2O (Complex 1) and [UO2(H2O)5]·[(UO2(TTTA))2] (Complex 2) based on a flexible 2,2',2''-[1,3,5-triazine-2,4,6-triyltris(thio)]trisacetic acid were synthesized using solvothermal techniques with different uranyl metal salts. The structure was explored using single-crystal diffraction and both of the compounds give a one-dimensional chain, then the two compounds were further characterized with IR, TG, UV–vis and other instruments. The fluorescence spectra of the compounds in different solvents have a slight change due to the transform of the electron state, and the luminescence properties showed that those one-dimensional uranium organic frameworks have a favorable sensitive response to Ru3+ and biomolecules (BSA, DA, AA, UA). It indicates that the host-guest interaction plays a crucial role in detecting these molecules, and the compounds could be used as an excellent sensor for the small molecules with a detect limitation of 33.03 ​μM (Complex 2 of UA).

Studies on new Schiff base complexes synthesized from d10 metal ions: Spectral, conductometric measurements, DFT and docking simulation

New Cd(II), Hg(II), Zn(II), UO2(II) complexes were prepared from cyclohexanone-[N-(3-hydroxy-2-naphthoyl)]hydrazone (H2CHNH) ligand by using ball milling technique. The formed compounds were elucidated by spectral (IR, NMR, SEM, EDX, Mass), analytical and conformational techniques. Schiff base ligand exhibited variable binding modes towards the metal ions within 1:1 M ratio mostly. Tetrahedral configuration was proposed for all d10 coordination systems except UO2(II) complex which basically desired to octahedral geometry. Conductometric measurements estimated association (KA, ΔGA) and formation constants (Kf and ΔGf) for Cd(II)- H2CHNH complex in solution. DFT/B3LYP computation was applied to optimize structures of compounds and extract important physical characteristics. In-vitro assay was applied to investigate antimicrobial, antioxidant and antitumor activity of new synthesizes. Best antioxidant and antitumor activity was recorded with Zn(II) complexes. For clarification, in-silico assay was executed by drug-like procedure as well as MOE-docking approach. Pharmit link was used to search on the most fitted drug-like to Zn(II) complexes. After 1,602,203 hits in MolPort library, the drug numbered by MolPort-000–810-252 was the most fitted one. MOE-docking was utilized with respect to Zn(II) complexes towards liver cancer cell proteins (3 h80, 4ndn & 8adh). [Zn(HCHNH)2].2H2O complex reveals high docking score in true interaction poses. Limited allosteric binding was recorded from O11, N15 and O42 sites towards amino acid residues or dummies. Finally, two Zn(II) complexes may be promising in controlling free radicals or liver cancer cells.

Synthesis, Crystal Structure and DNA-Binding Study of a New Zinc(II) Complex Based on 2,6-Bis(imino)pyridyl Ligand

A new zinc complex [Zn(L1)Cl2]2‧CH3OH‧2H2O (complex 1), where L1 stands for 2,6-Bis{[(4-ethylphenyl)imino]ethyl}pyridine (L1) has been synthesized and characterized. The crystal structure of L1 and complex 1 have been determined by single-crystal X-ray diffraction. Both compounds crystallize in the monoclinic P21/c space group. For the ligand L1, the crystal parameters are a = 16.7487(7) A, b = 5.8177(3) A, c = 21.8427(10) A, β = 104.1350(10)° and Z = 4. For complex 1, the crystal parameters are a = 8.0216(14) A, b = 13.433(2) A, c = 24.640(4) A, β = 90.223(3)° and Z = 2. In the crystal structure of complex 1, L1 acts as a tridentate ligand and coordinated with Zn1 with three nitrogen atoms. Together with two chlorine atoms, Zn1 atom is five-coordinated in a trigonal bipyramidal geometry. Hydrogen bonds play great role in the crystal structure of complex 1 and form a two-dimensional network. Furthermore, the DNA-binding property of complex 1 with fish sperm DNA (FS-DNA) has been investigated by electronic absorption titration. The result suggests that complex 1 might interact with FS-DNA via groove binding mode. The single crystals of 2,6-Bis{[(4-ethylphenyl)imino]ethyl}pyridine (L1) and it’s Zinc(II) complex [Zn(L1)Cl2]‧CH3OH‧H2O (1) were determined. In the crystal structure of complex 1, Zn1 atom is five-coordinated in a trigonal bipyramidal geometry. A two-dimensional network is formed by hydrogen bonds. DNA-binding study indicated that complex 1 interact with FS-DNA via groove binding mode.

Iron(III), copper(II), cadmium(II), and mercury(II) complexes of isatin carbohydrazone Schiff base ligand (H3L): Synthesis, characterization, X‐ray diffraction, cyclic voltammetry, fluorescence, density functional theory, biological activity, and molecular docking studies

A series of some transition metal, Fe(III), Cu(II), Cd(II), and Hg(II), complexes withN′,2‐bis((Z)‐2‐oxoindolin‐3‐ylidene)hydrazine‐1 carbohydrazide (H3L) ligand have been synthesized, and their structures were elucidated based on their spectral analyses (Fourier transform infrared [FT‐IR],1H nuclear magnetic resonance (NMR) and13C NMR, UV‐visible (UV‐Vis), electron spin resonance (ESR), powder X‐ray diffraction [XRD], and mass spectroscopy), elemental analyses, conductance, and magnetic susceptibility measurements. The structures of the H3L ligand and its metal complexes were optimized using the DMol3tool in the material studio package. The ligand behaves as binegative N2O3pentadentate in [Fe(HL)(Cl)]·2H2O complex, mononegative N2O3pentadentate in [Cu(H2L)(OAc)]·2H2O complex, mononegative N2O tridentate in [Cd(H2L)2]·H2O complex, and finally, neutral N2bidentate in [Hg(H3L)(Cl)2]·2H2O complex. Coats–Redfern and Horowitz–Metzger methods were used to estimate the various thermodynamic and kinetic parameters. Cyclic voltammetry of the ligand in the absence and presence of Cd(II) and Hg(II) ions was studied. Fluorescence studies were performed in DMSO and showed that Cu(II) ions quench the fluorescence spectrum of the free ligand, whereas Cd(II) ions enhance it. The in vitro antimicrobial activities of the free ligand and its complexes against different bacterial strains and fungiCandida albicanswere screened using agar‐disc diffusion techniques. The antioxidant potentials of the isolated compounds were also screened by employing SOD and ABTS free radical scavenging methods. Molecular docking studies were performed using Auto‐Dock tools to predict the best binding mode and predominant binding interactions.

Studying of physicochemical properties of Coumarin based Nano-complexes for biomedical applications

Novel Schiff base ligand based on coumarin precursor was prepared by the condensation of 3-acetyl coumarin with 3-aminophenol. The newly synthesized Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) complexes were characterized by elemental analysis, molar conductance, spectroscopic techniques (IR,1H NMR, mass spectrometry, UV–Vis), and thermal (TG/DTG) to predict their structures. The results data displays octahedral complexes with 1M:1L ratio. The IR confirmed that the ligand coordinated to the metal ions in tridentate mode with ONO coordination sites. The complexes decomposed with three to five steps within the temperature range 30-900 C. Additionally, mass spectra of the ligand and its Cu(II) complex offer well matching data with calculated value. The molar conductivity values pointed out that the complexes were non electrolytes. Molecular optimization of prepared compositions at DFT/ LANL2DZ level, besides Molecular docking between Schiff base ligand (HL) and the receptors of breast Cancer were executed. Additionally, antibacterial activity has been evaluated against Streptococcus aureus and Escherichia coli. Additionally, fungicidal activity was screened in vitro against Aspergillus flavus and Candida albicans, using the disc diffusion method. The [Co(HL)Cl2.H2O].4H2O complex exhibits the highest antimicrobial effect against Streptococcus aureus with inhibition area 17mm, while against Escherichia coli it records 14mm, and 12mm against Candida albicans . The [Mn(L)Cl2.H2O].4H2O complex showing the lowest IC50 against human cancer (MCF-7 cells viability) with 22.2 µg/ml.

Evaluating mutual influences of cation-π interactions and H-bonding: Cases of indole and BN-indole

An understanding of how various cations and water molecules form complexes with BN-indoles, inorganic counterparts of indole, may provide vital insights for its applications in biology as a motif of unnatural tryptophan. In this paper, we study mutual influences of the hydrogen bond (H-bond) and cation–π interactions in various complexes of indole and BN-indole with Li+ and H2O.Using the second-order symmetry-adapted perturbation theory (SAPT2), we determine the strength of both interactions and obtain their energy constituents. It has been established that the substitution of a CC bond with a BN one in the indole molecule does not lead to a significant drop of Li+ interaction energy (Eint). Moreover, Eint values for Li+ and indole + H2O and BN-indole + H2O complexes further increase, and the stabilization reaches 6.41–8.09 kcal/mol. Eint for a H2O molecule and Li+@indole and Li+@BN-indole complexes also increases, and the enhancement is calculated to be 5.93–7.50 kcal/mol. The quantum theory of atoms in molecules (QTAIM) approves the existing of H-bonds, and using topological parameters we calculate H-bonding energies, which are in a good accordance with the SAPT2 results. The complementary independent gradient model (IGM) technique helps to visualize 3D regions of non-covalent interactions and serves as an additional indicator of both types of the interplay. Finally, the basic regularities in mutual strengthening of H-bonds and cation–π interactions have been established. We believe that some theoretical aspects, derived in the present work, will be useful for the employment of biologically relevant molecules with new physical and chemical properties introduced via BN-CC substitution.

SYNTHESIS, STRUCTURE, AND STUDY OF THE BIOLOGICAL ACTIVITY OF Co(II), Ni(II), AND Cu(II) COMPLEXES WITH AN ENAMINEDIONE DERIVATIVE

[Cu(L)2] (1), [Co(L)2] (2), [Ni(L)2]·H2O (3) complexes where L is 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dionate are synthesized. Single crystals of complexes 1-3 are obtained. According to X-ray crystallographic data, in the Co and Ni complexes, a coordination polyhedron N2O4 is a distorted octahedron, and in the Cu complex, N2O2 is a distorted square. L is a tridentate ligand coordinated by oxygen atoms of carbonyl and methoxy groups as well as the nitrogen atom of the amide group. The cytotoxic properties of 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dione and respective complexes are studied on the Hep2 cell line (human laryngeal carcinoma). The compounds are shown to not exhibit cytotoxic properties in the studied concentration range (1-50 μM). Antibacterial, protistocidal, and fungistatic properties of HL, its structural analogue 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione (HL1), and complexes on their base are also studied. The antibacterial activity of HL and [Co(L1)2(C2H5OH)2] against S. aureus, of HL1 and [Co(L)2] against E. coli is revealed within 25-30% of the activity of reference drugs (ciprofloxacin, furazolidone). The [Ni(L1)2(C2H5OH)2] complex is found to have a pronounced protistocidal activity. Furthermore, the behavior of the [Ni(L)2]·H2O complex in phosphate buffered saline is analyzed at storage times t = 0 h, 24 h, 48 h and also in an aqueous solution at different pH values.

Synthesis, Structure and In Vitro Anticancer Activity of Pd(II) Complex of Pyrazolyl-s-Triazine Ligand; A New Example of Metal-Mediated Hydrolysis of s-Triazine Pincer Ligand

The square planar complex [Pd(PT)Cl(H2O)]*H2O (HPT: 6-(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine-2,4(1H,3H)-dione) was obtained by the reaction of 2-methoxy-4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine (MBPT) pincer ligand with PdCl2 in a molar ratio (1:1) under thermal conditions and using acetone as a solvent. The reaction proceeded via C-N cleavage of one C-N moiety that connects the pyrazole and s-triazine combined with the hydrolysis of the O-CH3 group. The reaction of the chloride salt of its higher congener (PtCl2) gave [Pt(3,5-dimethyl-1H-pyrazole)2Cl2]. The crystal structure of [Pd(PT)Cl(H2O)]*H2O complex is stabilized by inter- and intra-molecular hydrogen bonding interactions. Hirshfeld analysis revealed that the H...H (34.6%), O...H (23.6%), and Cl...H (7.8%) interactions are the major contacts in the crystal. The charges at Pd, H2O, Cl and PT are changed to 0.4995, 0.2216, −0.4294 and −0.2917 instead of +2, 0, −1 and −1, respectively, using the MPW1PW91 method. [Pd(PT)Cl(H2O)]*H2O complex has almost equal activities against MDA-MB-231 and MCF-7 cell lines with IC50 of 38.3 µg/mL.

Improving the surface morphology and crystallite size of isonicotinohydrazide based binuclear Cr(III), Zn(II) and Sn(IV) complexes after irradiation with γ-rays

In this work, binuclear Cr(III), Zn(II) and Sn(IV) complexes with: (Z)-N'-(4-methoxybenzylidene)isonicotinohydrazide (L) have been prepared and well assigned and then exposed to gamma ray irradiation with dose up to 100 kGy using Indian 60Co γ-ray cell type GE-4000 A. The structural properties of the synthesized compounds and the structural modifications of the irradiated samples were studied by analytical, magnetic, molar conductance measurements, different spectral (FT-IR, 1H NMR, UV–Vis), powder XRD and thermogravimetry (TG) techniques. The data show that all complexes are dinuclear, Cr(III) complex supposed in distorted teteragonal geometry and Zn(II) complex supposed in distorted square planar geometry have the formula [Cr2L(OH)4]Cl2(1) and [Zn2LCl2(H2O)2]Cl2.3H2O (2), respectively and Sn(IV) has distorted octahedral geometry and the formula is Sn2LCl2(OH)4(H2O)2]Cl2.H2O(3), no geometry change was detected upon irradiation. The XRD of both non-irradiated and irradiated complexes indicate that they are in a nanometer range. A reduction in average crystallite size was observed for irradiated Cr(III) complex. Scanning electron microscopy (SEM) micrographs of [Cr2L(OH)4]Cl2 complex (1) show improving of its crystallinity after γ-irradiation. Further, the solid electrical conductivity of [Zn2LCl2(H2O)2]Cl2.3H2O complex (2) before and after γ-irradiation has been investigated, both samples behaved like insulator. The antimicrobial screening for all metal complexes before and after γ-irradiation was achieved against pathogenic bacteria Staphylococcus aureus as Gram +ve bacteria, Escherichia coli as Gram -ve bacteria and Candida albicans as fungal strain. The results pointed that the metal complexes have moderate antimicrobial activity compared to the standards and in some cases γ-irradiation enhances antimicrobial activity.

Iron(III) and cobalt(III) complexes with pentadentate pyridoxal Schiff base ligand – structure, spectral, electrochemical, magnetic properties and DFT calculations

Three complexes, [FeLCl]Cl·H2O, [Co2L2H3O2]Cl·4.8H2O, and [CoLN3], where L2– is the dianion of an asymmetric propyl-ethyl pentadentate Schiff base ligand condensed from pyridoxal and N-(2-aminoethyl)propane-1,3-diamine, have been synthesized and characterized by elemental analysis, FT-IR and mass spectroscopy. Crystal structures of the complexes along with the Schiff base were determined by X-ray diffraction. 1HNMR spectrum of the Schiff base has been obtained. The coordination polyhedra of all three complexes can be expressed as distorted octahedra. Magnetic investigations of [FeLCl]Cl·H2O complex confirmed high-spin state over the whole temperature range (5–300 K) and allowed the evaluation of the axial zero-field splitting (ZFS) parameter D = –0.97 cm−1, intermolecular exchange parameter zj́ = –0.88 cm−1 and temperature-independent paramagnetism χTIM = 0.00025 cm3mol−1. The low-spin state of Co(III) was stabilized in diamagnetic [Co2L2H3O2]Cl·4.8H2O and [CoLN3] complexes. Redox potentials of the Schiff base and the complexes were investigated by cycling voltammetry on the GC electrode in dry acetonitrile. The experimental magnetic properties of the complexes [FeLCl]Cl·H2O and [CoLN3] were compared with the theoretical ones calculated using density functional theory (DFT).

THERMALLY GUIDED DEHYDRATION OF BINUCLEAR [Ni2(en)2(H2O)6(pyr)]·4H2O COMPLEX: A FURTHER INSIGHT

Thermally prompted dehydration of binuclear [Ni2(en)2(H2O)6(pyr)]·4H2O complex occurs within a 326 K to 410 K temperature region, presenting an asymmetrical DSC peak. The process is endothermal and results in the loss of 10 molecules of water accounting for 26.8% of the total mass of the sample. Values of the apparent activation energy of 71 kJ/mol and 93 kJ/mol were determined by using Kissinger's and the isoconversional KAS approach, respectively. The probable reaction mechanism was determined by Dollimore's analysis. Deconvolution of the experimental DSC peak on different heating rates shows that the mechanism of dehydration changes with the change in the heating regime. Using the linear compensation effect, values of invariant activation energy of 61 kJ/mol as well as of Arrhenius pre-exponential factor of 6·107 min-1 were determined.

Synthesis and corrosion resistance properties of novel conjugated polymer-Cu2Cl4L3 composites

A novel conjugated polyaniline (PANI)-[Cu2Cl4(m-aminophenylbenzimidazole)3] hybrid nanocomposites were prepared by using novel benzoyl peroxide as an organic oxidant by Inverse emulsion polymerization technique. The FTIR spectra of nanocomposites revealed the vibrational bands due to N–H stretching (3437 cm−1), quinoid (1487 cm−1) and benzenoid ring stretching (1384 cm−1). The conductivity of nanocomposites increases with PANI content. TGA thermogram nanocomposites (50/50) undergoes two-step weight loss in the temperature range 38–279 °C and 279–791 °C for first and second with a mass loss of 18 and 42% respectively. Thermograms reveal that the thermal stability of pure polyaniline was slightly enhanced by the incorporation of [Cu2Cl4L3]·2H2O complex. The formation of PANI-[Cu2Cl4L3]·2H2O nanocomposite was confirmed by FESEM pictures. Potentiodynamic polarization results show that the prepared nanocomposite shows mixed type corrosion inhibitor in 0.1 M HCl on steel-316 surface.

Synthesis, crystal structures, anticancer activities and molecular docking studies of novel thiazolidinone Cu(II) and Fe(III) complexes targeting lysosomes: special emphasis on their binding to DNA/BSA.

Novel [CuL2Cl]Cl·H2O (1) and [FeL2Cl2]Cl·MeOH·CHCl3·H2O (2) complexes of (Z)-N'-((E)-3-methyl-4-oxothiazolidin-2-ylidene)picolinohydrazonamide (L) as antitumor agents were designed and synthesized in order to explore DNA and serum albumin interaction. X-ray diffraction revealed that both 1 and 2 were a triclinic crystal system with P1̄ space group, which consisted of a positive electric main unit, a negative chloride ion and some solvent molecules. The complexes with DNA and bovine serum albumin (BSA) were studied by fluorescence and electronic absorption spectrometry. The results indicated that there was moderate intercalative binding mode between the complexes and DNA with Kapp values of 2.40 × 105 M-1 (1) and 6.49 × 105 M-1 (2). Agarose gel electrophoresis experiment showed that both 1 and 2 exhibited obvious DNA cleavage activity via an oxidative DNA damage pathway, and the cleavage activities of 1 were stronger than those of 2. Cytotoxicity assay showed that 1 had a more effective antitumor activity than 2. The two complexes were bound to BSA by a high affinity and quenched the fluorescence of BSA through a static mechanism. The thermodynamic parameters suggested that hydrophobic interactions played a key role in the binding process. The binding energy xpscore of 1 and 2 were -10.529 kcal mol-1 and -10.826 kcal mol-1 by docking studies, and this suggested that the binding process was spontaneous. Complex 1 displayed a lysosome-specific targeting behavior with a Pearson coefficient value of 0.82 by confocal laser scanning microscopy (CLSM), and accumulated in the lysosomes, followed by the disruption of lysosomal integrity.

A smart sensing triazine hexacarboxylic metal–organic skeleton material: synthesis, structure and multifunctional fluorescence detector

A novel lanthanide metal organic framework [(NH2(Me)2)]6·[Tb3(TDPAT)2(μ2-O)1.5]·3EtOH·7.5H2O (complex 1) was constructed via the reaction of 5,5′,5′′-(1,3,5-triazine-2,4,6-triyltriimino) tris(azanediyl)triisophthalate (H6TDPAT) and TbCl3·6H2O.