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The inhibition efficiency and adsorption affinity were investigated for two novel compounds, namely: 6-methoxy-2-naphthyl-[2, 2’-bithiophene]-5-carboxamidine hydrochloride salt (MA-1440) and 5'-(4-chlorophenyl)-2, 2’-bifuran-5-carboxamidine hydrochloride salt (MA-1456). The inhibition study was conducted on carbon steel surface in 1.0 M HCl with different inhibitor doses and different temperature levels, to investigate the optimum dose and preferable temperature. The performed investigation included chemical, electrochemical, instrumental, and quantum computation techniques. A chemical technique was accomplished by using weight-loss measurements. Different factors were studied using weight-loss measurements in order to reach the maximum inhibition efficiency. The adsorption study revealed that the examined inhibitors obey the Langmuir adsorption isotherm and are chemically adsorbed on the steel surface. The electrochemical measurements were accomplished through the electrochemical impedance (EIS) and potentiodynamic polarization (PDP) techniques. Based on the electrochemical measurements, the examined compounds were categorized as mixed inhibitors. The instrumental examination using different techniques namely: scanning electron microscope (SEM), energy dispersive X-ray (EDX), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) confirmed that the considered inhibitors are excellently adsorbed over the carbon steel surface. The extent of the adsorption affinity of these compounds on the carbon steel surface was studied theoretically using quantum computations and Monte Carlo simulation. The theoretical investigation results of quantum chemistry were validated with those obtained by chemical and electrochemical methodologies. All investigations prove that, the tested compounds were adsorbed chemically on the steel surface and achieved maximum inhibition efficiency of, 94.69% and 90.85% for M-1440 and MA-1456, respectively, at the optimum concentration 3010-6 mol. L-1 and temperature 328 K.

Design of the structure of nanosized photo-catalysts is an interesting research area to achieve high performance of their catalytic property. Nano-scaled single crystals of {[Ni(EN)4(NCS)2]} coordination complex (EN = ethyl nicotinate), CC1 and the nano-sized particles, CC1\ are synthesized by self-assembly and ultrasonic radiation methods, respectively. The structure comprises two crystallographically different and chemically identical Ni atoms adopting [NiN6] octahedron geometry. The structure of CC1 propagates via 1D-zegzag chains which extend in 3D- fashion via strong H-bonds. The chemical structure and morphology of CC1 and CC1\ are characterized by single crystal and powder X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and spectroscopic methods. The heterogeneous catalytic and photo-catalytic activity of CC1 and CC1\ exhibit very efficient catalytic activity towards degradation of indigo carmine dye (IC) within very short times under UV-light or ultrasonic radiation. The good limit of detection and the high quenching efficiency of CC1 towards selective quantitative fdetermination of nitrobenzene (NB) and Fe3+ ions support its behavior as an efficient luminescent sensor.

The supramolecular complexes (SC) of the type [Me2SnCl2L], L = 2,2′-bipyridine (2,2′-bpy), SC 1, 4,4′-bipyridine (4,4′-bpy), SC 2, and (1,10-phenanthroline), SC 3, have been synthesized and structurally characterized by elemental analysis, FT-IR, UV–Vis, 1H and 13C NMR spectra and X-ray single crystal. The X-ray data of SC 1 and SC 2 exhibited 1:1 stoichiometry for the dimethyltin dichloride: bipodal ligand. The structure of SC 1 extends along the a-axis in a parallel way forming 1D-chains via H-bonds while they further propagate creating 2D-network via extensive H-bonds. The extending structure of the SC 2 along the a-axis consists of parallel 1D-chains via H-bonds creating the A … A … A fashion. Molecular modeling studies of SC 3 indicated that Sn(IV) center acquires N2C2Cl2 octahedral geometry. The tested compounds SC 1, SC 2 and SC 3 were found to inhibit cell proliferation and induce high percent of apoptotic towards human breast adenocarcinoma (MCF7), liver carcinoma (HEPG2), colorectal carcinoma (HCT-116), cervical carcinoma (HELA) and prostate cancer (PC3) cell lines in vitro model within short times of treatment. The anti-Oxidant and anti-hemolytic assays employ that SC 1 exhibits moderate antioxidant activity as well as the most potent anti-hemolysis activities compared with ascorbic acid. The antimicrobial assessment has been also studied by disc diffusion method.

The supramolecular polymer of the type [Me2SnCl2L], 1, L = 2,2'-bipyridine (2,2'-bpy), has been synthesized by the reaction of dimethyltin (IV) dichloride and 5-nitroisophthallic acid in the presence of sodium ethoxide and 2,2'-bpy. The compound was structurally characterized by elemental analysis, FT-IR spectra and X-ray single crystal. The x-ray data exhibited 1:1 stoichiometry for the dimethyltin dichloride: 2,2'-bpy ligands. The structure of 1 extends along the a-axis in a parallel way forming 1D-chains via H-bonds while they further propagate creating 2D- network via extensive H-bonds. The biological activity against some fungi and bacterial microorganisms has been also studied.

Two new supramolecular coordination polymers namely {[Cd(NA)2(H2O)]}, SCP 1 and {[Pb(NA)2]}, SCP 2, (NA = nicotinate ligand) were synthesized by self–assembly method and structurally characterized by different analytical and spectroscopic methods. Single-crystal X-ray diffraction showed that SCP 1 extend in three dimensions containing bore structure where the 3D- network is constructed via interweaving zigzag chains. The Cd atom coordinates to (O4N2) atoms forming distorted-octahedral configuration. The structure of SCP 2 extend down the projection of the b-axis creating parallel zigzag 1D-chains connected by μ2-O2 atoms and H-bonds forming a holodirected lead (II) hexagonal bi-pyramid configuration. SCP 2 extend to 3D-network via coordinate and hydrogen bonds. The thermal stability, photoluminescence properties, photocatalytic activity for the degradation of methylene blue dye (MB) under UV-irradiation and sunlight irradiation were also studied.

Long chain aliphatic diamine, 1,7-diaminoheptane (DAHP), was selected as template for creation of novel nano-scaled 3D-guest-host- supramolecular coordination polymer (SCP); ∞3[(Cu3(CN)3)2.(DAHP)], 1. Crystal structure of SCP 1 consists of new bi-fold [Cu3(CN)3]2 fragments containing tetrahedral copper(I) atoms which are arranged in unique way to create 3D-structure exhibiting wide cavities enable to encapsulate the long chain DAHP as guest molecule. The topology of 1 had been elucidated by spectroscopic methods, elemental analysis, transmission electron microscopy (TEM) and scanning electron microscope (SEM). The nanosized SCP1 exhibits excellent catalytic activity towards mineralization of methyl violet (MV), methylene blue (MB) and indigo carmine (IC) dyes using H2O2 as oxidant within very short times. Scavenger techniques and disodium terephthalate (NaTA) as selective photoluminescence prob of hydroxyl radical had been utilized to elucidate mineralization mechanism. Nano-SCP 1 exhibits sigmoidal dose-response inhibition of cells viability giving low IC50 values for the tested cell as well as was examined for rate erythrocyte hemolysis and antioxidant activity utilizing ABTS assay. Also, SCP1 exhibits good antimicrobial activity due to the low MIC values keeping it a promising drug candidate for the treatment of the tested bacterial and fungal infections.

Yellow prismatic nanoparticles of the supramolecular coordination polymer (SCP) [Cu6(CN)7(C6H12N4)2(OH3)], 1 were obtained by the reaction of K3[Cu(CN)4] and hexamethylenetetramine (hmt) in presence of Me3SnCl at ambient conditions. The X-ray structure of 1 consists of many rhombic [(Cu)2µ3–(CN)2] motifs which construct eight fused cyclic rings accommodating two hmt ligands. The copper atoms exhibit pseudo-tetrahedral configuration. The cyanide ligands create the bifurcated µ3-CN bridges. The [(Cu)2µ3–(CN)2] motifs causes expansion of the structure of 1 to three dimensions while extensive H-bonds play an essential role in packing structure. SCP 1 was used as an efficient heterogeneous catalyst for oxidative mineralization of acid blue-92 (AB-92), textile dye, with H2O2. The study aimed to investigate the efficiency of recycled the catalyst 1 and the mechanism of degradation of AB-92. The morphological feature of the SCP 1 as a catalyst before and after catalysis was examined by high resolution transmission electron microscope (TEM).

{[Co(CN)6(Me3Sn)3(H2O)].(qox)} host-guest supramolecular coordination polymer, SCP1, is synthesized by adding K3[Co(CN)6], quinoxaline (qox) and Me3SnCl using the self-assembly method at ambient conditions. X-ray diffraction (XRD) of single crystal of SCP1 indicates that the structure consists of [Co(CN)6(H2O)] building blocks which construct the 3D-host network connected by the Me3Sn+ cations and accommodate qox guest molecule. The nanosized particles of {[Co (CN)6(Me3Sn)3(H2O)].(qox)}; SCP1∖ are obtained by sono-chemical method while the morphology was examined by powder X-ray diffraction (PXRD) and transition electron microscopy (TEM). The fluorescence property of SCP1∖ has been examined which exhibits high luminescent selective sensory towards nitrobenzene, Hg+1, Fe3+ and Pb2+ ions. SCP1 and SCP1∖ are tested as heterogeneous catalysts for degradation of phenol under UV- and ultrasonic radiation. The catalysts cause efficient degradation of phenol which was enhanced by radiation. The mechanism of degradation was suggested and discussed in detail.

An “on–off–on” switchable optical chemosensor namely: 5-(4-dimethylamino-phenyl)-1-pyridin-2-yl-penta-2,4-dien-1-one, DMAC and its metal complexes were synthesized and characterized. The optical studies of DMAC were presented, and reveal several interesting points when different metal ions such as Co(II), Ni(II) and Cu(II) were added. The results showed that the absorption and emission spectra are very sensitive to the used metal ions. Detectable cation-induced effects were observed on adding different concentrations of the used metal ions to DMAC, with instantaneous color change. The origin of the color change was attributed to modulation of the intramolecular charge transfer of chemosensor DMAC upon effective coordination with the used metal ions through nitrogen atoms of pyridine moiety along with oxygen of carbonyl group. Furthermore, ethylene diamine tetraacetic acid (EDTA) can selectively turn on the absorption and emission spectra of DMAC complex induced by the used metal ions (“on–off–on” type sensor). The stability constants, K , have been determined and confirming the formation of 1:1 complexes between DMAC and the used metal ions. Solid Co(II), Ni(II) and Cu(II) complexes were synthesized and characterized by a set of chemical and spectroscopic measurements using elemental analysis, electrical conductance, mass spectra, magnetic susceptibility and spectral techniques (FT-IR, UV–vis, 1 H NMR). The structure of metal complexes has been also theoretically studied using molecular mechanics (MM + ). The structures obtained were minimized with a semi-empirical (PM3) method. The synthesized DMAC and its complexes were screened for their biological activities.

N-(pyridine-2-ylmethylene)benzo[d]thiazol-2-amine Schiff base (L) and its Cu(II), Fe(III), Co(II), Ni(II) and Zn(II) complexes were synthesized and characterized by a set of chemical and spectroscopic measurements using elemental analysis, electrical conductance, mass spectra, magnetic susceptibility and spectral techniques (IR, UV–Vis, 1H NMR). Elemental and mass spectrometric data are consistent with the proposed formula. IR spectra confirm the bidentate nature of the Schiff base ligand. The octahedral geometry around Cu(II), Fe(III), Ni(II) and Zn(II) as well as tetrahedral geometry around Co(II) were suggested by UV–Vis spectra and magnetic moment data. The thermal degradation behavior of the Schiff base and its complexes was investigated by thermogravimetric analysis. The structure of the Schiff base and its transition metal complexes was also theoretically studied using molecular mechanics (MM+). The obtained structures were minimized with a semi-empirical (PM3) method. The in vitro antitumor activity of the synthesized compounds was studied. The Zn-complex exhibits significant decrease in surviving fraction of breast carcinoma (MCF 7), liver carcinoma (HEPG2), colon carcinoma (HCT116) and larynx carcinoma (HEP2) cell lines human cancer.

N-(thiophen-2-ylmethylene)benzo[d]thiazol-2-amine Schiff base (L) derived from 2-aminobenzothiazole and 2-thiophenecarboxaldehyde was synthesized and characterized using elemental analysis, IR, mass spectra, (1)H NMR and UV-vis spectra. Its complexes with Cu(II), Fe(III), Ni(II) and Zn(II) were prepared and isolated as solid products and characterized by elemental and thermal analyses, spectral techniques as well as magnetic susceptibility. The IR spectra showed that the Schiff base under investigation behaves as bidentate ligand. The UV-vis spectra and magnetic moment data suggested octahedral geometry around Cu(II) and Fe(III) and tetrahedral geometry around Ni(II) and Zn(II). In view of the biological activity of the Schiff base and its complexes, it has been observed that the antimicrobial activity of the Schiff base increased on complexation with the metal ion. In vitro antitumor activity assayed against five human tumor cell lines furnished the significant toxicities of the Schiff base and its complexes.

The straightforward self-assembly reaction of R3Sn+ and [Fe(CN)6]3− affords three-dimensional (3-D) coordination polymers [(n-Bu3Sn)2(R3Sn)Fe(CN)6] n , R = n-Bu(I) or Ph(II). The architecture of these coordination polymers is closely related to zeolite and acts as a host with wide internal cavities or channels capable of encapsulating voluminous organic compounds. Aniline derivatives acting as guest are encapsulated within the cavities of the 3-D-polymeric hosts I and II by tribochemical reaction producing host–guest supramolecular polymers. The structures and physical properties of these hosts and their host–guest systems were investigated by elemental analysis, X-ray powder diffraction, IR, UV-vis, EPR, and magnetic measurements. The morphology of these systems was examined by scanning electron microscopy (SEM). The interesting feature of these host–guest supramolecular polymers is the enhanced electrical conductivities over those of the 3-D-coordination polymeric hosts upon encapsulation of conductive ...

The syntheses and crystal structures of novel supramolecular coordination polymers (SCPs) of AgCN with bipodal ligands; 4,4′-bipyridine (bpy), trans-1,2-bis(4-pyridyl)ethylene (tbpe) and 1,2-bis(4-pyridyl)ethane (bpe) are reported. The syntheses were affected in H2O/acetonitrile/NH3 media at room temperature. SCP [(AgCN)2 · bpy] (1) is monoclinic and crystallizes in the space group P21/c, a = 9.0565(4) A, b = 16.0063(8) A, c = 9.1361(4) A, β = 110.51° and Z = 4. SCP [(AgCN)3 · (tbpe)2 · H2O] (2) is triclinic and crystallizes in the space group P 1 ¯ , a = 9.8427(4) A, b = 10.3596(4) A, c = 14.0864(6) A, α = 98.873°, β = 101.739°, γ = 95.506° and Z = 2. SCP [(AgCN)4 · bpe] (3) is monoclinic and crystallizes in the space group P21/c, a = 10.1872(5) A, b = 9.1610(5) A, c = 14.4862(6) A, β = 130.00(18)° and Z = 2. The 3D-topolgies of 1–3 resulted from the bridging action of the bipodal ligands and the argentophilic interactions as well as extensive H-bonding and π–π stacking.

Three supramolecular coordination polymers (SCPs) [(AgSCN)2L] {L = 4,4′-bipyridine (bpy) (1), trans-1,2-bis(4-pyridyl)ethylene (tbpe) (2) and phenazine (phenz) (3)} have been synthesized and structurally characterized by single-crystal X-ray diffraction. Synthesis was affected in H2O/acetonitrile/NH3 media at room temperature. The bpy, tbpe and phenz bipodal ligands adopt different conformations which would affect the skeleton of the (AgSCN)n building blocks that allow the interconnection of the (AgSCN)n fragments and propagation of the network structure in three dimensions. Supramolecular interactions such as hydrogen-bonding, argentophilic interaction and π–π stacking play an important role in the assembly of these coordination polymers.