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The synthesis, photophysical and photochemical properties of nonperipherally (α) mercaptoquinoline substituted Zn(II), TiO(IV) and Mg(II) and quaternized Zn(II) phthalocyanines are described for the first time. These complexes (2 to 5) and their precursor are characterized by elemental analysis, FT-IR, ¹H NMR, electronic spectroscopy as well as mass spectroscopy. Complexes 2, 4 and 5 have good solubility in organic solvents such as CHCl₃, DCM, DMSO, DMF, THF and toluene and are not aggregated in all solvents within a wide concentration range. Complex 3 showed very good solubility in water as well as DMSO and DMF. General trends are described for singlet oxygen, photodegradation and fluorescence quantum yields of these complexes in DMSO and DMF. While complex 2 has higher singlet oxygen and fluorescence quantum yields than 3, 4 and 5, complex 4 has higher fluorescence quantum yields in DMF and DMSO than 2, 3 and 5. The effect of the solvents and metal on the photophysical and photochemical parameters of the metallophthalocyanines are also reported.

We report here the preparation (in "one-pot") of a tetra-β″-sulfoleno-meso-aryl-porphyrin in about 80% yield by using an optimized modification of Lindsey's variant of the Adler–Longo approach. The Zn(II)-, Cu(II)- and Ni(II)-complexes of the symmetrical porphyrin were prepared and characterized spectroscopically. Crystal structures of the fluorescent Zn(II)- and of the non-fluorescent Ni(II)-tetra-β″-sulfoleno-meso-aryl-porphyrinates showed the highly substituted porphyrin ligands to be nearly perfectly planar. The Zn(II)-complex of this porphyrin has been used as a thermal precursor of a reactive diene, and — formally — of lateral and diagonal bis-dienes, of a tris-diene and of a tetra-diene, which all underwent [4 + 2]-cycloaddition reactions in situ with a range of dienophiles. Thus, the tetra-β″-sulfoleno-meso-aryl-porphyrin and its metal complexes represent reactive building blocks, "programmed" for the syntheses of symmetrical and highly functionalized porphyrins.

5,15-substituted porphyrins are valuable compounds in bioorganic and materials chemistry. A new synthesis has been developed that employs 1,9-diformylation of a dipyrromethane, conversion of the diformyldipyrromethane to the bis(imino) derivative, and reaction of the bis(imino)dipyrromethane + a dipyrromethane to give the zinc-porphyrin bearing trans-AB-substituents. 1,9-diformylation was achieved via Vilsmeier reaction. Imination was achieved by treatment of the 1,9-diformyldipyrromethane with excess amine under neat conditions at room temperature. The porphyrin-forming reaction was carried out over 2 h in refluxing ethanol containing zinc acetate exposed to air. Oxidation of the intermediate porphyrinogen occurs aerobically. A complex composed of two bis(imino)dipyrromethanes and two zinc atoms was observed to form reversibly during the course of the reaction. A set of zinc-porphyrins with trans-AB-, A₂-, or A-substituents has been prepared in yields of ~30% (without detectable scrambling) with straightforward purification. The reaction is applicable to A/B substituent combinations of aryl/aryl, aryl/alkyl, and aryl/H.

The five possible non-peripherally substituted zinc(II) phthalocyanines with different molecular symmetries (Pc1–Pc5) were synthesized from statistical condensation of the phthalonitrile derivatives (A and B). 2-[2-(2-ethoxyethoxy)ethoxy]-1-[2-((2-ethoxyethoxy)-ethoxy)ethoxymethyl]ethyloxy and 2′-[(tert-butoxycarbonyl)amino]ethoxy groups were used as substituents. The structures of the new compounds were characterized using elemental analysis and spectroscopic data including IR, ¹H and ¹³C NMR, electronic absorption and mass spectra. The photophysical and photochemical properties of these new compounds were investigated in DMSO. The effect of the molecular symmetry of phthalocyanine molecules on the photophysical and photochemical properties was compared in this study.

The structure and chemistry of mammalian metallothioneins (MTs) with divalent (Zn^II, Cd^II) and monovalent (Cu^I) metal ions pertinent to their role in biological systems are discussed. In human, four MT isoforms designated MT-1 through MT-4 are found. The characteristic feature of these cysteine- and metal-rich proteins is the presence of two metal-thiolate clusters located in independent protein domains. The structure of these clusters is highly dynamic, allowing a fast metal exchange and metal transfer to modulate the activity and function of zinc-binding proteins. Despite the fact that the protein thiolates are involved in metal binding, they show a high reactivity toward electrophiles and free radicals, leading to cysteine oxidation and/or modification and metal release. The unusual structural properties of MT-3 are responsible for its neuronal growth inhibitory activity, involvement in trafficking of zinc vesicles in the central nervous system (CNS), and protection against copper-mediated toxicity in Alzheimer's disease. MT-1/MT-2 also play a role in cellular resistance against a number of metal-based drugs.

Tetra and octa substituted novel zinc(II) phthalocyanines (3a and 5a) bearing carbazole groups were synthesized by cyclotetramerization of respective phthalonitrile derivatives (3 and 5). The zinc(II) phthalocyanines (3a and 5a) were converted into the water-soluble quaternized derivatives (3b and 5b) by utilizing dimethylsulphate as quaternizing agent. The synthesized novel compounds were confirmed thruogh FT-IR, UV-vis and MALDI-TOF mass spectroscopic data and elemental analysis as well. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen generation) properties of new phthalocyanines were determined in dimethylsulfoxide (DMSO). The photophysical and photochemical results were compared according to the number of the carbazole groups on the phthalocyanine core. Additionaly, in vitro photocytotoxicity of the targeted compounds were examined against to hepato cellular carcinoma (HuH-7) cancer cell line for determination of their photosensitizing ability.

Four asymmetric Zn(II) phthalocyanines (Pc1–Pc4) bearing a carboxylic acid group in the peripheral position have been designed and synthesized to investigate the influence of the distance between COOH group and the phthalocyanine core on their photophysical and photochemical properties. The novel phthalocyanine complexes were characterized by ${}^{\mathrm{\text{1}}}$H, ${}^{\mathrm{\text{13}}}$C NMR, IR, and UV-vis spectroscopies, elemental analysis and matrix-assisted laser desorption ionization mass spectrometry (MALDI). The aggregation behavior, photophysical and photochemical properties such as fluorescence lifetime and quantum yields and singlet oxygen quantum yields of Pc1–Pc4 were explored in tetrahydrofuran (THF) to the determination of the potential use of these novel phthalocyanines as photosensitizers for different applications such as photovoltaic technologies and photodynamic therapy (PDT). Pc1–Pc4exhibited high singlet oxygen generation quantum yields (0.84, 0.66, 0.88 and 0.65, respectively). Fluorescence quantum yields could be obtained for Pc1, Pc2, Pc3 and Pc4 (0.13, 0.31, 0.10 and 0.25, respectively) in THF.

Synchrotron radiation X-ray fluorescence (SR-XRF) using high energy incident X-rays was combined with micro-PIXE to analyze the renal distribution of Rb and essential elements in immature rats. The Rb concentrations in the kidneys of newborn (1 week old) and young (3 weeks old) rats were 4.19 ± 0.71 and 4.13 ± 0.30 µg/g, respectively, similar to those of adult rats. Rubidium as well as Zn was detected more in the cortex than the medulla, while Fe was concentrated in the outermost areas of the medulla of newborn rats. The renal structures of young rats achieved adult zonation into the cortex, the outer medulla and the inner medulla. Rubidium was high in the outer stripe of the outer medulla. Further analysis at higher resolution revealed Rb in the proximal tubules in the innermost part of the cortex. These results indicated that Rb was distributed downstream of the proximal tubules. This profile was similar to that of potassium, an Rb congener.

Zn powder has been used for many years as anticorrosive pigments in various paints. In this work, the nano-sized Zn powder was synthesized by wire explosion method in deionised water and ethanol. The morphology of the prepared powders was observed by field emission-scanning electron microscopy (FE-SEM) and the oxidation of the powders was determined using energy-dispersive X-ray spectroscopy (EDS). The size of particles was estimated from transmission electron microscopy (TEM) and FE-SEM. Dispersion properties of the as-prepared Zn nanoparticles in ethanol were evaluated by Turbiscan lab device. It is found that Zn nanoparticle prepared in ethanol had spherical shape with average particles size ~150 nm while the one prepared in water had a mixture of hexagonal and spherical shape. Ethanol can reduce the oxidation of Zn nanoparticles in comparison with water. Stability of Zn nanoparticles dispersed in ethanol exhibited the agglomeration in the dispersion.

The synthesis, spectroscopic and electrochemical properties of new phthalocyanines bearing four morpholine and four chloro units is reported. Two-step synthesis involved efficient nucleophilic substitution of 4,5-dichlorophthalonitrile as the key step. The free-base phthalocyanine and its several complexes have been characterized using UV-vis, IR, ¹HNMR, ¹³CNMR and mass spectroscopic data. Voltammetric and spectroelectrochemical studies show that while cobalt phthalocyanine gives both metal- and ring-based, diffusion-controlled, multi-electron and reversible/quasi-reversible redox processes, other complexes give ring-based, multi-electron and reversible/quasi-reversible redox processes.

Metallothioneins (MTs) are cysteine-rich proteins capable of scavenging free radicals and sequestering metal ions. In the liver, these proteins are involved in copper and zinc metabolism, in the chelation of heavy metals, and in protection against oxidative damage. Because of their properties, MTs are involved in many liver diseases, which can be sorted into the following:

1. Metal storage liver diseases. Zinc, which is an important anticopper agent for Wilson's disease, acts by increasing the concentration of MTs in the enterocytes, thereby reducing metal absorption. Copper also accumulates in the liver in cholestatic diseases, in which MTs are reportedly overexpressed and induced by ursodeoxycholic acid (UDCA), the main drug used to treat cholestasis. The role of MTs in hemochromatosis, an iron-accumulating disease, has yet to be established; but in animal models, it has been suggested that zinc, by increasing MT concentration, could exert a beneficial effect.

2. Toxic liver diseases. By sequestering metal ions and scavenging free radicals, MTs protect against damage caused by exogenous toxic substances, such as cadmium and arsenic, and by the toxic effects on hepatocytes of ethanol and at in alcoholic and nonalcoholic liver diseases.

3. Chronic viral hepatitis. By lowering the inflammatory injury, MTs have a protective action against chronic liver damage; a relationship has also been described between MTs and the severity of liver disease and the response to therapy.

4. Hepatocellular carcinoma. MTs are downexpressed and inversely correlated with tumor stage; an inverse correlation has also been reported between MT concentrations and response to platinum chemotherapy.

Given the ability of zinc to strongly induce MT synthesis, zinc supplementation could be useful not only in Wilson's disease, but also in other liver diseases in which MTs exert a protective effect.

We prepared zinc-containing TCP/HAp ceramics (Zn-TCP/HAp) in the shape of disk, and examined the effect of zinc on the osteogenic differentiation of cultured marrow cells on the surface of Zn TCP/HAp. Fresh marrow cells were obtained from the femora of Fischer rats and cultured in a medium containing 15% fetal bovine serum to reach confluent. After trypsinization, the cells were seeded at 20×10³ cells/16 mm ϕ on Falcon tissue wells with the ceramic disk for subculture. Just before the cell seeding, three different disks (TCP/HAp containing 0, 0.126, or 0.316 wt% Zn) were placed in the wells. After 2 weeks of subculture in the presence of β-glycerophosphate, vitamin C phosphate, and dexamethasone, the cells were stained for alkaline phosphatase (ALP). The ALP positive area on the Zn-TCP/HAp disk was expanded with an increase in Zn content, as covering almost the entire surface of the Zn-TCP/HAp disk of 0.316 Zn wt%. The results indicate that the Zn doped TCP/HAp ceramics stimulate osteoblastic differentiation in cultured marrow stromal cells.

Zinc was doped into β-tricalcium phosphate up to 10 mol %. The zinc-doped tricalcium phosphate (ZnTCP), tricalcium phosphate (TCP) and hydroxyapatite (HAP) powders were mixed with a total metal-per-phosphate ratio fixed at 1.60, followed by being sintered into a dense body at 1100°C for 1 hour to make a ZnTCP and HAP composite ceramic (ZnTCP/HAP). The ZnTCP/HAP released calcium, phosphate and zinc ions for at least 30 days in a physiological saline solution.

No inhibitory effect of ZnTCP/HAP on the proliferation of MC3T3-E1 cells was observed up to a zinc content of 1.26 wt%. A relative cell growth rate increased significantly in a zinc content of the ZnTCP/HAP from 0.6 to 1.26 wt%. The ZnTCP and the ZnTCP/HAP ceramics were implanted in the femora of New Zealand White rabbits for four weeks. Histological and histomorphometrical investigation on the undecalcified sections revealed that the bone formation area per area of medullary cavity increased by 51 % (p=0.509, n=6) around the ZnTCP/HAP implants with a zinc content of 0.316 wt%, compared with the control.

The prostate is an accessory sex organ that secretes essential components of semen. High levels of Zn are found both in the prostate and its secretion. In the present study, the effects of environmental stress on zinc levels in the prostate were examined in Wistar male rats exposed to tributyltin chloride (TBTC), an environmental toxicant, by inductively coupled argon plasma–mass spectrometry (ICP-MS) for determination of Zn concentration in lobe-dissectioned specimens and micro-PIXE analysis for determination of site-specific distribution of Zn in prostatic sections. A single oral administration of TBTC to rats at a dose of 90 μmol/kg resulted 14 days later in a decrease in the Zn level in the dorsolateral prostate but not the ventral prostate. The TBTC did not affect the weight of the prostate tissue. Micro-PIXE imaging found Zn both in the lumen and the epithelium of the lateral prostatic tubules. PIXE spot analysis revealed that the epithelium of the control rat contained levels of Zn 4–fold higher than in the lumen and that Zn in the epithelium decreased selectively after TBTC exposure.

The pancreas is a large gland capable of both exocrine and endocrine functions; it releases digestive enzymes into the duodenum and hormones into the bloodstream. It is known that Zn plays a key role in the synthesis and action of insulin, one of the pancreatic hormones. However, elemental profiles of the pancreas are not well understood. Here, we examined precise distributions of elements in the pancreas of newborn and young rats by scanning microbeam particle induced X-ray emission (micro PIXE) analysis and compared the results to those of adult animals.

Micro PIXE analysis revealed a site-specific distribution of elements in the two major compartments of the pancreas, the exocrine (acinar tissue) and the endocrine portions (islets of Langerhans). The Zn concentrations in the pancreas of the newborn (six days), young (three weeks), and adult rats (ten weeks) were 11.3 ± 2.5 μg/g wet weight, 7.26 ± 0.36 μg/g wet weight, and 10.8 ± 1.1 μg/g wet weight, respectively. In newborn and young rats, Zn was detected mainly in the islets of Langerhans, while K and P were distributed more to the acinar tissues than the islet cells. The site-specific distributions of K, P, and Zn were more obvious in the adult animals.

The hard tissues of cephalopod, namely statoliths were analyzed with PIXE for the Japanese common squid Todarodes pacificus of the Sea of Japan origin in order to examine the relationship between the amount of trace elements in statoliths and environmental temperature of the squid habitat. Calcium, iron, zinc. copper and strontium were detected in the statoliths. Negative relationship was observed between Sr concentration in statoliths and environmental temperature. On the contrary to Sr, Fe and Zn concentration in statoliths related positively with environmental temperature. These observations revealed that the statoliths would be a useful thermometer for reconstructing the environmental temperature of cephalopod habitat as seen in the hard tissues of other marine organisms.

This review is in general about group 12 elements and their small microclusters. In this part, after presenting an extensive literature survey of the electric dipole polarizability studies of the Zn, Cd and Hg atoms, we specifically target zinc-containing small clusters, beginning with the Zn₂ dimer, the Zn₃ trimer, higher Zn_n clusters and the neutral, cationic and anionic zinc oxide clusters: ZnO, ZnO⁺ and ZnO^-. We tabulated experimental and theoretical results for the spectroscopic constants (dissociation energy D_e or D₀, bond length r_e, fundamental frequency w_e, anharmonicity constant w_ex_e and dipole moment μ_e) of the diatomic clusters and the first and second ionization potentials IP₁ and IP₂ and electron affinity EA of the species reviewed.

The crystal structure of zinc metal deviates from the ideal hexagonal close packing structure by a significantly increased axial ratio (c/a). The local atomic structure of zinc metal is investigated using the total scattering atomic pair distribution function (PDF) analysis based on X-ray powder diffraction data collected at ambient conditions. The X-ray total scattering PDF analysis confirms that the crystal structure of zinc can be described in terms of wurtzite structure, but with an anomalously atomic displacement parameters $U_{33}$, indicating a significant displacement disorder along the $c$-axis. For the long $r$-range PDF refinements, the thermal motion of zinc shows a notable anisotropy as expressed by the ratio $U_{33}$/$U_{11}$ of 2.5 at ambient conditions. This average distortion level along the $c$-axis, was not reflected locally for the features below 5.0 Å as it fits the high $r$ region. Based on PDF refinements over different $r$-ranges, we measure an interesting increase of the $U_{33}$ value with decreasing the $r$-range of the refinement. This suggests that the local structure features in zinc metal differ from the average structure ones.

The synthesis of a phthalocyanine-porphyrin heteropentamer (zinc(II) tetra(5-phenoxy-10,15,20-triphenylporphyrin)) zinc(II) phthalocyanine, (ZnPc-(ZnTPP)₄), containing four units of zinc tetraphenylporphyrin linked to a central zinc phthalocyanine macrocycle via an ether linkage is reported. The photophysical parameters of the pentamer are reported in toluene and dimethyl sulfoxide (DMSO). The observed differences in the fluorescence behavior of the pentamer in the two solvents is explained in terms of emission from different states; charge transfer state in DMSO and locally excited state in toluene. The rate constants for fluorescence, intersystem crossing, internal conversion, and of charge and energy transfer are reported for the pentamer. Quantum yields for fluorescence, internal conversion, triplet state and of charge and energy transfer are also reported for the pentamer, ZnPc-(ZnTPP)₄ and the mixture of ZnPc and ZnTPP. The latter two parameters are higher in the pentamer compared to a mixture containing ZnPc and ZnTPP.

The novel zinc(II) phthalocyanine complexes bearing tetra or octa-[7-oxy-3-(3′,4′,5′-trimethoxyphenyl)coumarin] moieties were synthesized for the first time in this study. These phthalocyanines were characterized by different spectroscopic methods such as FT-IR, ¹H NMR, electronic absorption spectra, MALDI-TOF mass and elemental analyses as well. The photochemical properties such as singlet oxygen generation, photostability and photophysical properties such as fluorescence quantum yields and lifetimes were investigated in $N$,$N$-dimethylformamide (DMF) solutions. The effect of the structure (the position and number of the coumarin groups on phthalocyanine framework) of novel phthalocyanines on these properties was also determined in this study.