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Artigos de revistas sobre o tema "Complexes de zinc"

Autor: Grafiati

Publicado: 23 de novembro de 2024

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1

Nabeshima, Tatsuya, Yusuke Chiba, Takashi Nakamura e Ryota Matsuoka. "Synthesis and Functions of Oligomeric and Multidentate Dipyrrin Derivatives and their Complexes". Synlett 31, n.º 17 (24 de julho de 2020): 1663–80. http://dx.doi.org/10.1055/s-0040-1707155.

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The dipyrrin–metal complexes and especially the boron complex 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) have recently attracted considerable attention because of their interesting properties and possible applications. We have developed two unique and useful ways to extend versatility and usefulness of the dipyrrin complexes. The first one is the linear and macrocyclic oligomerization of the BODIPY units. These arrangements of the B–F moieties of the oligomerized BODIPY units provide sophisticated functions, such as unique recognition ability toward cationic guest, associated with changes in the photophysical properties by utilizing unprecedented interactions between the B–F and a cationic species. The second one is introduction of additional ligating moieties into the dipyrrin skeleton. The multidentate N2Ox dipyrrin ligands thus obtained form a variety of complexes with 13 and 14 group elements, which are difficult to synthesize using the original N2 dipyrrin derivatives. Interestingly, these unique complexes exhibit novel structures, properties, and functions such as guest recognition, stimuli-responsive structural conversion, switching of the optical properties, excellent stability of the neutral radicals, etc. We believe that these multifunctional dipyrrin complexes will advance the basic chemistry of the dipyrrin complexes and develop their applications in the materials and medicinal chemistry fields.1 Introduction2 Linear Oligomers of Boron–Dipyrrin Complexes3 Cyclic Oligomers of Boron–Dipyrrin Complexes4 A Cyclic Oligomer of Zinc–Dipyrrin Complexes5 Group 13 Element Complexes of N2Ox Dipyrrins6 Chiral N2 and N2Ox Dipyrrin Complexes7 Group 14 Element Complexes of N2O2 Dipyrrins8 Other N2O2 Dipyrrin Complexes with Unique Properties and Functions9 Conclusion

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Schäfer, Sebastian, Ralf Köppe, Michael T. Gamer e Peter W. Roesky. "Zinc–silylene complexes". Chemical Communications 50, n.º 77 (15 de agosto de 2014): 11401. http://dx.doi.org/10.1039/c4cc04714a.

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3

Nieuwenhuizen, Peter J. "Zinc accelerator complexes." Applied Catalysis A: General 207, n.º 1-2 (fevereiro de 2001): 55–68. http://dx.doi.org/10.1016/s0926-860x(00)00613-x.

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Midlej, Victor, Felipe Rubim, Wilmer Villarreal, Érica S. Martins-Duarte, Maribel Navarro, Wanderley de Souza e Marlene Benchimol. "Zinc-clotrimazole complexes are effective against Trichomonas vaginalis". Parasitology 146, n.º 9 (3 de maio de 2019): 1206–16. http://dx.doi.org/10.1017/s003118201900043x.

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AbstractTrichomonas vaginalis is a protozoan parasite that causes trichomoniasis in humans, the most prevalent non-viral sexually transmitted disease (STD). Imidazole compounds are used for the treatment of trichomoniasis, and metronidazole is the most commonly prescribed. However, these compounds can lead to parasite resistance and unwanted side effects. Therefore, there is a need for an alternative treatment for this disease. Here, we explored the potential of clotrimazole (CTZ) and zinc compounds, as well as CTZ complexed with zinc salts ([1] acetate [Zn(CTZ)2(Ac)2] and [2] a chloride [Zn(CTZ)2Cl2] complexes) against T. vaginalis. We synthesized the zinc complexed CTZ compounds and determined their concentration values that inhibited parasite growth by 50% (IC50). We used scanning and transmission electron microscopy to visualize the ultrastructural alterations induced by CTZ and their zinc complexes. The incubation of the parasites with [Zn(CTZ)2(Ac)2] complex inhibited their growth, yielding an IC50 of 4.9 µm. Moreover, there were changes in the shape of treated parasites, including the formation of surface projections that subsequently detached from the cell, in addition to changes in the hydrogenosomes, endoplasmic reticulum and Golgi complex. We found [Zn(CTZ)2(Ac)2] to be a highly effective compound against T. vaginalis in vitro, suggesting its potential utility as an alternative chemotherapy for trichomoniasis.

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Müller-Hartmann, A., e H. Vahrenkamp. "Binary zinc-oligophosphate complexes". Inorganica Chimica Acta 300-302 (abril de 2000): 531–36. http://dx.doi.org/10.1016/s0020-1693(99)00614-3.

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6

Meyer, Nils, e Peter W. Roesky. "Chiral Aminotroponiminate Zinc Complexes". Organometallics 28, n.º 1 (12 de janeiro de 2009): 306–11. http://dx.doi.org/10.1021/om800858t.

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7

Datta, Simmi, Michael T. Gamer e Peter W. Roesky. "TADDOLate complexes of zinc". Dalton Transactions, n.º 13 (2008): 1761. http://dx.doi.org/10.1039/b715123c.

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Marks, Sebastian, Ralf Köppe, Tarun K Panda e Peter W Roesky. "Unprecedented Zinc-Borane Complexes". Chemistry - A European Journal 16, n.º 24 (12 de maio de 2010): 7096–100. http://dx.doi.org/10.1002/chem.201000571.

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Sudbrake, Claas, Bodo Müller e Heinrich Vahrenkamp. "Hexakis(alcohol)zinc Complexes". European Journal of Inorganic Chemistry 1999, n.º 11 (novembro de 1999): 2009–12. http://dx.doi.org/10.1002/(sici)1099-0682(199911)1999:11<2009::aid-ejic2009>3.0.co;2-n.

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Walz, Rainer, Michael Ruf e Heinrich Vahrenkamp. "(Pyrazolylborato)zinc−Aldehyde Complexes". European Journal of Inorganic Chemistry 2001, n.º 1 (janeiro de 2001): 139–43. http://dx.doi.org/10.1002/1099-0682(20011)2001:1<139::aid-ejic139>3.0.co;2-6.

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Amiri, Asghar, Ian M. Comeau e Alison Thompson. "Heteroleptic zinc dipyrromethene complexes". Journal of Heterocyclic Chemistry 43, n.º 2 (março de 2006): 431–35. http://dx.doi.org/10.1002/jhet.5570430225.

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Alsfasser, Ralf, Anne K. Powell e Heinrich Vahrenkamp. "Functional Tetrahedral Zinc Complexes". Angewandte Chemie International Edition in English 29, n.º 8 (agosto de 1990): 898–99. http://dx.doi.org/10.1002/anie.199008981.

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Albedyhl, Sabine, David Schnieders, Attila Jancsó, Tamás Gajda e Bernt Krebs. "Heterodinuclear Zinc(II)−Iron(III) Complexes and Dinuclear Zinc Complexes as Models for Zinc-Containing Phosphatases". European Journal of Inorganic Chemistry 2002, n.º 6 (junho de 2002): 1400–1409. http://dx.doi.org/10.1002/1099-0682(200206)2002:6<1400::aid-ejic1400>3.0.co;2-q.

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Tau, Prudence, Abimbola O. Ogunsipe, Suzanne Maree, M. David Maree e Tebello Nyokong. "Influence of cyclodextrins on the fluorescence, photostability and singlet oxygen quantum yields of zinc phthalocyanine and naphthalocyanine complexes". Journal of Porphyrins and Phthalocyanines 07, n.º 06 (junho de 2003): 439–46. http://dx.doi.org/10.1142/s1088424603000562.

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The effects of formation of cyclodextrin inclusion complexes on the photochemical and photophysical properties of zinc phthalocyanine ( ZnPc ) and various peripherally substituted zinc phthalocyanines as well as zinc naphthalocyanine ( ZnNPc ) are investigated. The cyclodextrins employed were the hydroxypropyl-γ-cyclodextrin and unsubstituted β-cyclodextrin. Job's plots were employed to confirm the stoichiometry of the inclusion complexes and showed 2:1 and 4:1 (cyclodextrin:phthalocyanine) inclusion behavior. The phthalocyanine inclusion complexes showed larger singlet oxygen quantum yield (ϕΔ) values when compared to the free phthalocyanines before inclusion, for complexes 1 (zinc naphthalocyanine), 2 (zinc tetranitrophthalocyanine) and 4 (zinc tetra-tert-butylphenoxyphthalocyanine). The fluorescence quantum yields generally remained unchanged following inclusion.

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Oh, Shin Bi, Jung Ah Kim, SuJi Park e Joo-Yong Lee. "Associative Interactions among Zinc, Apolipoprotein E, and Amyloid-β in the Amyloid Pathology". International Journal of Molecular Sciences 21, n.º 3 (25 de janeiro de 2020): 802. http://dx.doi.org/10.3390/ijms21030802.

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Zinc and apolipoprotein E (apoE) are reportedly involved in the pathology of Alzheimer’s disease. To investigate the associative interaction among zinc, apoE, and amyloid-β (Aβ) and its role in amyloid pathogenesis, we performed various biochemical and immunoreactive analyses using brain tissues of Tg2576 mice and synthetic Aβ and apoE peptides. On amyloid plaques or in brain lysates of Tg2576 mice, apoE and Aβ immunoreactivities increased after zinc chelation and were restored by its subsequent replacement. Zinc depletion dissociated apoE/Aβ complexes or larger-molecular sizes of Aβ oligomers/aggregates into smaller-molecular sizes of apoE and/or Aβ monomers/complexes. In the presence of zinc, synthetic apoE and/or Aβ peptides aggregated into larger-molecular sizes of oligomers or complexes. Endogenous proteases or plasmin in brain lysates degraded apoE and/or Aβ complexes, and their proteolytic activity increased with zinc depletion. These biochemical findings suggest that zinc associates with apoE and Aβ to encourage the formation of apoE/Aβ complexes or large aggregates, raising the deposition of zinc-rich amyloid plaques. In turn, the presence of abundant zinc around and within apoE/Aβ complexes may block the access or activity of Aβ-degrading antibodies or proteases. These results support the plausibility of chelation strategy aiming at reducing amyloid pathology in Alzheimer’s disease.

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Maciejewska, Magdalena, Anna Sowińska e Agata Grocholewicz. "Zinc Complexes with 1,3-Diketones as Activators for Sulfur Vulcanization of Styrene-Butadiene Elastomer Filled with Carbon Black". Materials 14, n.º 14 (7 de julho de 2021): 3804. http://dx.doi.org/10.3390/ma14143804.

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Zinc oxide nanoparticles (N-ZnO) and zinc complexes with 1,3-diketones of different structures were applied instead of microsized zinc oxide (M-ZnO) to activate the sulfur vulcanization of styrene-butadiene rubber (SBR). The influence of vulcanization activators on the cure characteristics of rubber compounds, as well as crosslink density and functional properties of SBR vulcanizates, such as tensile properties, hardness, damping behavior, thermal stability and resistance to thermo-oxidative aging was explored. Applying N-ZnO allowed to reduce the content of zinc by 40% compared to M-ZnO without detrimental influence on the cure characteristic and performance of SBR composites. The activity of zinc complexes in vulcanization seems to strongly depend on their structure, i.e., availability of zinc to react with curatives. The lower the steric hindrance of the substituents and thus the better the availability of zinc ions, the greater was the activity of the zinc complex and consequently the higher the crosslink density of the vulcanizates. Zinc complexes had no detrimental effect on the time and temperature of SBR vulcanization. Despite lower crosslink density, most vulcanizates with zinc complexes demonstrated similar or improved functional properties in comparison with SBR containing M-ZnO. Most importantly, zinc complexes allowed the content of zinc in SBR compounds to be reduced by approximately 90% compared to M-ZnO.

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Vishwkarma, Arti, A. K. Srivastava, O. P. Pandey e S. K. Sengupta. "Zinc(II) Complexes of Schiff Bases Derived from Bis-(2-hydrazino-1,3,4-thiadiazole-5- yl)Arene/Alkanes: Synthesis, Spectral Characterization and Biological Properties". Asian Journal of Chemistry 34, n.º 8 (2022): 2035–40. http://dx.doi.org/10.14233/ajchem.2022.23718.

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A novel series of zinc(II) complexes of type [ZnL(H2O)2], has been synthesized by the reaction of zinc(II) acetate dihydrate with Schiff bases (H2L) derived from bis-(2-hydrazino-1,3,4-thiadiazole-5- yl)arene/alkanes and 2-hydroxynaphthaldehyde/3,5-dichlorosalicyldehyde in presence of a base. The structures of all the zinc complexes were proposed by elemental analysis and spectroscopic data (IR, 1H, 13C NMR). TGA investigations were carried out to confirm the presence of coordinated water molecules in the zinc complexes. The powder crystal structure of one particular zinc complex has been analyzed by XRD diffraction method and SEM studies have been carried out to investigate the surface morphology. The biological studies reveal that the synthesized zinc complexes possess good antimicrobial properties against different species of pathogenic fungi and bacteria.

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Zhang, Wei-Guang. "Microwave-Assisted Synthesis, Characterization, Crystal Structures and Antibacterial Activities of Zinc Complexes Derived from 5–Bromo-2-((cyclohexylimino)methyl)phenol". Acta Chimica Slovenica 70, n.º 3 (20 de setembro de 2023): 421–29. http://dx.doi.org/10.17344/acsi.2023.8144.

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A dinuclear zinc complex [Zn2L2] (1), and four mononuclear zinc complexes [ZnBr2(LH)2] (2), [ZnCl2(LH)2] (3), [Zn(LH)2(NCS)2] (4) and [ZnI(CH3OH)L] (5), have been prepared from the Schiff base 5-bromo-2-((cyclohexylimino) methyl)phenol (HL) by microwave irradiation method. All the zinc complexes were characterized by CHN elemental analyses, infrared and electronic spectra. Structures of the complexes were further studied by single crystal X-ray determination, which reveals that all the zinc atoms in the complexes are in tetrahedral geometry. The halide and pseudohalide anions are preferred co-ligands in the preparation of such complexes with binary ligands. The biological activity of the complexes on the bacterial strains Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was evaluated. The complexes bearing halide and pseudohalide ligands show effective activities on the bacteria strains.

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Varbanov, Sabi, Elena Russeva e Andrei Ganchev. "Zinc Complexes of Dimethyl(phthalimidomethyl)phosphine Oxide". Zeitschrift für Naturforschung B 49, n.º 2 (1 de fevereiro de 1994): 258–62. http://dx.doi.org/10.1515/znb-1994-0218.

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A series o f zinc complexes of dimethyl(phthalimidomethyl)phosphine oxide (DPPO, L) have been synthesized: ZnX2L2, where X = Cl, Br, I or NO3. The complexes are characterized by elemental analysis, infrared and 1H NMR spectra and X-ray powder analysis. Infrared spectral data show that L is coordinated to zinc via the phosphoryl oxygen atom. The zinc halide complexes are found to be isostructural, while the pattern o f Zn(NO3)2L2 differs considerably from those o f halide complexes.

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20

de Moraes, Josué, Bruno S. Dario, Ricardo A. A. Couto, Pedro L. S. Pinto e Ana M. da Costa Ferreira. "Antischistosomal Activity of Oxindolimine-Metal Complexes". Antimicrobial Agents and Chemotherapy 59, n.º 10 (3 de agosto de 2015): 6648–52. http://dx.doi.org/10.1128/aac.01371-15.

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ABSTRACTIn recent years, a class of oxindole-copper and -zinc complex derivatives have been reported as compounds with efficient proapoptotic activity toward different tumor cells (e.g., neuroblastomas, melanomas, monocytes). Here we assessed the efficacy of synthesized oxindole-copper(II), -zinc(II), and -vanadyl (VO2+) complexes against adultSchistosoma mansoniworms. The copper(II) complexes (50% inhibitory concentrations of 30 to 45 μM) demonstrated greater antischistosomal properties than the analogous zinc and vanadyl complexes regarding lethality, reduction of motor activity, and oviposition.

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Chen, Lei, Xuanri Shen e Guanghua Xia. "Effect of Molecular Weight of Tilapia (Oreochromis Niloticus) Skin Collagen Peptide Fractions on Zinc-Chelating Capacity and Bioaccessibility of the Zinc-Peptide Fractions Complexes in Vitro Digestion". Applied Sciences 10, n.º 6 (17 de março de 2020): 2041. http://dx.doi.org/10.3390/app10062041.

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To investigate the effect of the molecular weight of tilapia skin collagen peptide fractions on their zinc chelation capacity and the bioaccessibility of their zinc complexes, we evaluated the zinc-chelating ability of different molecular weight peptide, the solubility, and the stability of the complexes during simulated in vitro digestion. Low molecular weight peptide (P1) exhibited a higher zinc-chelating ability, which can be attributed to the variety of metal chelate amino acid residues. The highest solubility and the lowest release of zinc during peptic digestion for the P1-zinc complex and the zinc binding to P1 were retained at approximately 50% after peptic-pancreatic digestion. Fourier transform infrared spectroscopy indicated the primary involvement of the N-H group in all peptide-zinc complexes. This finding suggests that low molecular weight peptidefraction with strong zinc chelation ability can be used as delivery agents to improve zinc bioaccessibility.

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22

Nakamura, Mizuki, Daigo Urakawa, Ziyu He, Isao Akagi, De-Xing Hou e Kozue Sakao. "Apoptosis Induction in HepG2 and HCT116 Cells by a Novel Quercetin-Zinc (II) Complex: Enhanced Absorption of Quercetin and Zinc (II)". International Journal of Molecular Sciences 24, n.º 24 (14 de dezembro de 2023): 17457. http://dx.doi.org/10.3390/ijms242417457.

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Quercetin forms complexes with various metals due to its structural attributes. It predominantly exhibits chelating activity at the 3-hydroxy/4-carbonyl group. Previously, coordination in synthetically obtained quercetin–zinc (II) complexes has been limited to this group. However, the expanded coordination observed in quercetin–iron complexes has opened avenues for diverse applications. Thus, synthesizing novel quercetin–zinc complexes with different coordination positions is a significant advance. In our study, we not only synthesized and comprehensively characterized a new quercetin–zinc (II) complex, Zn-Q, but also evaluated the structure and bioactivity of chelate complexes (Q+Zn) derived from co-treatment in cell culture mediums. The structure of the new compound Zn-Q was comprehensively characterized using 1D 1H and 2D correlation spectroscopy (COSY), nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV-Vis), electrospray ionization mass spectrometer (ESI-MS), and X-ray diffraction analysis (XRD) analysis. Subcellular localization and absorption of these zinc (II) complexes were determined using the ZnAF-2 DA zinc ion fluorescence probe. Throughout the experiments, both Zn-Q and Q+Zn exhibited significant antioxidant, cell growth inhibitory, and anticancer effects in HepG2 and HCT116 cells, with Zn-Q showing the highest potential for inducing apoptosis via the caspase pathway. Tracking intracellular zinc complex absorption using zinc fluorescent probes revealed zinc (II) localization around the cell nucleus. Interestingly, there was a proportional increase in intracellular quercetin absorption in conjunction with zinc (II) uptake. Our research highlights the advantages of quercetin complexation with zinc (II): enhanced anticancer efficacy compared to the parent compound and improved bioavailability of both quercetin and zinc (II). Notably, our findings, which include enhanced intracellular uptake of both quercetin and zinc (II) upon complex formation and its implications in apoptosis, contribute significantly to the understanding of metal–polyphenol complexes. Moving forward, comprehensive functional assessments and insights into its mechanism of action, supported by animal studies, are anticipated.

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Zhong, W., Guo Qing Zhong, Y. Zhang e Q. Zhong. "Solvent-Free Synthesis and Characterization of the Zn(II) Complexes with Amino Acid Schiff Base". Advanced Materials Research 455-456 (janeiro de 2012): 740–45. http://dx.doi.org/10.4028/www.scientific.net/amr.455-456.740.

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Three zinc (II) complexes of the amino acid Schiff base were synthesized by the one step reaction of amino acid with aldehyde, zinc acetate in solvent-free. The compositions and structures of the complexes were characterized by elemental analyses, FTIR, XRD, TG-DSC. The compositions of the complexes are ZnL•nH2O (L = sal-leu, sal-ala, van-leu; sal = salicylaldehyde; van = vanillic aldehyde; leu = leucine; ala = alanine). Infrared spectra of the complexes indicate that the Schiff base ligands are formed, zinc ion is coordinated to the Schiff base ligands as terdentate with O, O and N donors from carboxylic, phenolic and imino groups respectively, the coordination numbers of zinc ion is four. The possible pyrolysis reactions in the thermal decomposition process of the complexes, the experimental and calculated percentage mass loss are also given.

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Santos Vieira, Ines dos, e Sonja Herres-Pawlis. "Novel Guanidine-Quinoline Hybrid Ligands and the Application of their Zinc Complexes in Lactide Polymerisation". Zeitschrift für Naturforschung B 67, n.º 4 (1 de abril de 2012): 320–30. http://dx.doi.org/10.1515/znb-2012-0405.

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The syntheses of the three new guanidine-quinoline hybrid ligands TMGmqu, DMEGmqu and TMGtbqu are reported. Zinc chlorido and triflato complexes with these ligands were obtained and structurally characterised by X-ray crystallography. In the chlorido complexes the zinc atom is coordinated by two chlorido ligands and the bidentate guanidine ligand in a distorted tetrahedron. Using zinc triflate, tetrahedral bis(chelate) complexes are formed, and the triflate anions serve only for charge compensation. All reported complexes show activity in the polymerisation of rac-lactide, with the chlorido complexes only showing a poor activity. With the bis(chelate) triflato complexes a high polymerisation activity with a slight heterotactic bias was observed. Kinetic studies reveal a firstorder chain growth reaction for the lactide polymerisation with all complexes.

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Xie, Hong, Sam H. Leung e Kevin M. Smith. "Syntheses and some chemistry of stable isoporphyrin systems". Journal of Porphyrins and Phthalocyanines 06, n.º 10 (outubro de 2002): 607–16. http://dx.doi.org/10.1142/s1088424602000750.

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Isoporphyrin zinc(II) complexes can be synthesized using the MacDonald ["2+2"] approach, with suitably substituted dipyrromethanes and 5,5-dialkyldipyrromethanes. The zinc(II) complexes are stable, show characteristic optical and 1 H NMR spectra, and have been characterized as perchlorate salts by X-ray diffraction. Attempts to prepare other metal salts of isoporphyrins ( Ni , Cu , Fe ), either by metalation during ring synthesis or by subsequent metalation of metal-free isoporphyrins, were unsuccessful. Evidence shows that a metal-free isoporphyrins can synthesized by demetalating the corresponding zinc(II) complexes with TFA. However, workup with base after the reaction must be avoided. The optical spectra of relatively unstable metal-free isoporphyrins (λ max ( CH 2 Cl 2) 430, 700 nm) are blue shifted relative to their zinc(II) complexes (λ max ( CH 2 Cl 2) 416, 731, 797 nm), and can be remetalated with zinc(II) acetate, to generate the fully characterized zinc(II) salts.

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Creaser, II, T. Komorita, AM Sargeson, AC Willis e K. Yamanari. "New Macrocyclic Complexes Derived From Cobalt(III) Cage Complexes". Australian Journal of Chemistry 47, n.º 3 (1994): 529. http://dx.doi.org/10.1071/ch9940529.

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The synthesis and partial characterization of several green complexes, derived from the products of the reactions between [Co(Cl2-sar)]3+ (Cl2-sar = 1,8-dichloro-3,6,10,13,16,19- hexaazabicyclo [6.6.6] icosane ) and zinc powder in water, are described. Most of the complexes appear to have [CoCl2(N4)] chromophores , where N4 denotes the tetraaza macrocyclic ligand , 6,13-dimethylene-1,4,8,11-tetraazacyclotetradecane (L1). For trans-[CoCl2(L1)]+, three isomers due to different configurations about the asymmetric nitrogen donor centres were obtained and characterized by the electronic absorption and 13C n.m.r. spectra. Their stereochemistry is discussed and compared with that of 1,4,8,11-tetraazacyclotetradecane on the basis of strain energy minimized calculations. A trans-[CoCl2(H2L2)]3+ complex containing a related macrocycle with a pendant ethane-1,2-diamine arm [H2L2+, 6-(4-ammonio-2-azoniabutyl)-13-methylene-1,4,8,11-tetraazacyclotetradecane] was also isolated and characterized by X-ray crystallographic analysis. All these molecules are derived from the decomposition of zinc alkyl complexes formed by oxidative addition of zinc to the parent [CoII(Cl2-sar)]2+ ion in aqueous solution.

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Chiu, Yu-Hung, Gregory J. Gabriel e James W. Canary. "Ternary Ligand−Zinc−Hydroxamate Complexes". Inorganic Chemistry 44, n.º 1 (janeiro de 2005): 40–44. http://dx.doi.org/10.1021/ic0493090.

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Liang, Lan-Chang, Wei-Ying Lee e Chen-Hsiung Hung. "Amido Phosphine Complexes of Zinc". Inorganic Chemistry 42, n.º 18 (setembro de 2003): 5471–73. http://dx.doi.org/10.1021/ic0346228.

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Hartman, U., e H. Vahrenkamp. "Zinc complexes of dipyridyl-triazoles". Inorganica Chimica Acta 239, n.º 1-2 (novembro de 1995): 13–17. http://dx.doi.org/10.1016/0020-1693(95)04712-3.

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Richburg, Lauakia M., Jamshaid A. Farouq, Christopher D. Incarvito, Arnold L. Rheingold* e Daniel Rabinovich*. "Zinc bis(pyrazolyl)silane complexes". Polyhedron 19, n.º 15 (julho de 2000): 1815–20. http://dx.doi.org/10.1016/s0277-5387(00)00470-8.

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Javed, Saba, e David M. Hoffman. "Synthesis of Zinc Hydrazonide Complexes". Inorganic Chemistry 47, n.º 24 (15 de dezembro de 2008): 11984–92. http://dx.doi.org/10.1021/ic801451v.

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Matsuda, Kenji, Kohsuke Takayama, Yoshihiro Shinkai e Masahiro Irie. "Photochromism of Diarylethene Zinc Complexes". Molecular Crystals and Liquid Crystals 431, n.º 1 (1 de junho de 2005): 429–32. http://dx.doi.org/10.1080/15421400590947009.

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Bonner, Emily S., James T. Engle, Saovalak Sripothongnak e Christopher J. Ziegler. "Zinc complexes of the carbahemiporphyrazines". Dalton Transactions 39, n.º 8 (2010): 1932. http://dx.doi.org/10.1039/b925669e.

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Müller, Bodo, e Heinrich Vahrenkamp. "Aldehyde Complexes of Zinc Halides". European Journal of Inorganic Chemistry 1999, n.º 1 (janeiro de 1999): 129–35. http://dx.doi.org/10.1002/(sici)1099-0682(199901)1999:1<129::aid-ejic129>3.0.co;2-p.

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35

Müller, Bodo, e Heinrich Vahrenkamp. "Zinc Complexes of Chelating Aldehydes". European Journal of Inorganic Chemistry 1999, n.º 1 (janeiro de 1999): 137–44. http://dx.doi.org/10.1002/(sici)1099-0682(199901)1999:1<137::aid-ejic137>3.0.co;2-t.

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36

Meyer, Nils, e Peter W. Roesky. "Enantiopure Salen-Type Zinc Complexes". Zeitschrift für anorganische und allgemeine Chemie 633, n.º 13-14 (outubro de 2007): 2292–95. http://dx.doi.org/10.1002/zaac.200700188.

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37

Gamer, Michael T., e Peter W. Roesky. "Bridged Aminotroponiminate Complexes of Zinc". European Journal of Inorganic Chemistry 2003, n.º 11 (junho de 2003): 2145–48. http://dx.doi.org/10.1002/ejic.200300008.

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38

Liao, Jian-Ming, Yu-Kai Chin, Yu-Ting Wu e Hsien-Hsin Chou. "Effect of regio-specific arylamine substitution on novel π-extended zinc salophen complexes: density functional and time-dependent density functional study on DSSC applications". RSC Advances 13, n.º 4 (2023): 2501–13. http://dx.doi.org/10.1039/d2ra07571g.

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39

Li, Tianshu, Stephan Schulz e Peter W. Roesky. "Synthesis, reactivity and applications of zinc–zinc bonded complexes". Chemical Society Reviews 41, n.º 10 (2012): 3759. http://dx.doi.org/10.1039/c2cs15343b.

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40

Inamdar, Poonam R., Jyotsna Hazarika, T. B. Sridharan e A. Sheela. "Synthesis and DNA Binding Study of Zinc (II) Co-Ordination Complexes". Advanced Materials Research 584 (outubro de 2012): 401–5. http://dx.doi.org/10.4028/www.scientific.net/amr.584.401.

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Since the discovery of cisplatin, transitional metal complexes have been proven to be potent DNA intercalating agents. As zinc being an active core of binding site of some metalloenzymes, the synthesis of structurally similar zinc (II) complexes is on the offing. They are found to be potent DNA intercalating and cleaving agents. Thus, the current study is focused on synthesis of zinc (II) complexes using amino acid / schiff bases as ligands. The complexes are characterized by FTIR, UV-Visible and mass spectral studies and assessed for their DNA binding study using λ DNA by Gel electrophoresis.

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41

Yadav, Ravi, Milena Dahlen, Akhil K. Singh, Xiaofei Sun, Michael T. Gamer e Peter W. Roesky. "Nonanuclear zinc–gold [Zn3Au6] heterobimetallic complexes". Dalton Transactions 50, n.º 24 (2021): 8558–66. http://dx.doi.org/10.1039/d1dt01396c.

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Heterobimetallic nonanuclear Zn–Au complexes are synthesized. The complexes comprise a trinuclear Zn core and six Au(i) moieties on the periphery. Photoluminescence of the Zn-metalloligand and the Zn–Au complex has also been studied.

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42

Golubeva, I. S., A. E. Barmashov, A. A. Rudakova, M. A. Baryshnikova, N. S. Rukk, A. Yu Skryabina e G. N. Apryshko. "Сytotoxicity of zinc (II) and cadmium (II) iodide complexes with antipyrine, caffeine and phenantroline". Russian Journal of Biotherapy 16, n.º 3 (30 de setembro de 2017): 75–78. http://dx.doi.org/10.17650/1726-9784-2017-16-3-75-78.

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Objective: to study the cytotoxic activity of the zinc (II) and cadmium (II) iodide complexes with antipyrine (AP), caffeine (caf) and 1,10-phenantroline (phen) in comparison with that of free ligands, zinc (II) and cadmium (II) iodides in vitro. Materials and methods. The cytotoxic activity of the zinc (II) and cadmium (II) iodide complexes with AP, caf and phen in comparison with that of free ligands, zinc (II) and cadmium (II) iodides was investigated by methylthiazole tetrazolium assay using 5 human tumor cell lines. Results. It has been found that all 3 cadmium complexes demonstrate cytotoxic activity towards all 5 cell lines with concentration of inhibition of 50 % cell growth 5.5-84.0 mkM. Cytotoxicity of the most active diiodo(1,10-phenantroline)cadmium was slightly above than that of the respective ligand. One zinc-containing complex (diiodo(1,10-phenantroline)zinc) demonstrated significant activity towards 3 cell lines. The Jurkat cells were the most sensitive to studied compounds. Conclusion. It seems that zinc (II) and cadmium (II) iodide complexes with organic ligands are promising ones as potential antitumor drugs for further investigations both in vitro and in vivo.

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Wang, Yun, Wenjuan Zhang, Pengjiang Zhu, Wei You, Xiaopan Xue, Rui Wang, Yanping Ma e Wen-Hua Sun. "Intensive Cycloalkyl-Fused Pyridines for Aminopyridyl–Zinc–Heteroimidazoles Achieving High Efficiency toward the Ring-Opening Polymerization of Lactides". Molecules 29, n.º 17 (31 de agosto de 2024): 4150. http://dx.doi.org/10.3390/molecules29174150.

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The model precatalyst sp3- and sp2-N dinitrogen-coordinated zinc–heteroimidazole has been used as an efficient catalyst for the ring-opening polymerization of cyclic esters. Subsequent to our exceptional active 5,6,7-trihydroquinolin-8-amine-zinc catalysts for the ring-opening polymerization (ROP) of ε-caprolactone, various pyridine-fused cycloalkanones (ring size from five to eight) are developed for the correspondent fused amine–pyridine derivatives and their zinc–heteroimidazole chloride complexes Zn1–Zn8 (LZnCl2) bearing N-diphenylphosphinoethyl pendants. Activated with two equivalents of LiN(SiMe3)2, the title zinc complexes efficiently promote the ROP of L-lactide (L-LA) in situ; among them, Zn4/2Li(NSiMe3)2 catalyzed 500 equivalent L-LA at 80 °C with 92% conversion in 5 min (TOF: 5520 h−1). Under the same conditions, the catalytic efficiency for the ROP of rac-LA by Zn1–Zn8/2Li(NSiMe3)2 was slightly lower than that for L-LA (highest TOF: 4440 h−1). In both cases, cyclooctyl-fused pyridyl–zinc complexes exhibited higher activity than others, while the cycloheptyl-fused zinc complexes showed the lowest activity. The microstructure analysis of the polymers showed they possessed a linear structure capped with CH3O as major and cyclic structure as minor. In this work, all the ligands and zinc complexes were well characterized by 1H/13C/31P NMR, FT-IR spectroscopy as well as elemental analysis.

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Heumen, Jeff Van, Toru Ozeki e Donald E. Irish. "A Raman spectral study of the equilibria of zinc bromide complexes in DMSO solutions". Canadian Journal of Chemistry 67, n.º 11 (1 de novembro de 1989): 2030–36. http://dx.doi.org/10.1139/v89-314.

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Using Raman spectroscopy, the stepwise formation of zinc bromide complexes in dimethylsulfoxide (DMSO) solution has been investigated. The presence of four different zinc bromide complexes is suggested and their Raman spectra have been extracted. The formation constant of each reaction has been estimated by the application of factor analysis to the spectra. The usual methods of factor analysis have been extended by the introduction of constraints imposed by the equilibria. Keywords: zinc bromide complexes, solvation in DMSO, Raman spectroscopy, factor analysis.

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45

Borràs, Jordi, Julie Foster, Roxana Kashani, Laura Meléndez-Alafort, Jane Sosabowski, Joan Suades e Ramon Barnadas-Rodríguez. "New Bioconjugated Technetium and Rhenium Folates Synthesized by Transmetallation Reaction with Zinc Derivatives". Molecules 26, n.º 8 (19 de abril de 2021): 2373. http://dx.doi.org/10.3390/molecules26082373.

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The zinc dithiocarbamates functionalized with folic acid 2Zn and 3Zn were synthesized with a simple straightforward method, using an appropriated folic acid derivative and a functionalized zinc dithiocarbamate (1Zn). Zinc complexes 2Zn and 3Zn show very low solubilities in water, making them useful for preparing Tc-99m radiopharmaceuticals with a potentially high molar activity. Thus, the transmetallation reaction in water medium between the zinc complexes 2Zn or 3Zn and the cation fac-[99mTc(H2O)3(CO)3]+, in the presence of the monodentate ligand TPPTS, leads to the formation of the 2 + 1 complexes fac-[99mTc(CO)3(SS)(P)] bioconjugated to folic acid (2Tc and 3Tc). In spite of the low solubility of 2Zn and 3Zn in water, the reaction yield is higher than 95%, and the excess zinc reagent is easily removed by centrifugation. The Tc-99m complexes were characterized by comparing their HPLC with those of the homologous rhenium complexes (2Re and 3Re) previously synthesized and characterized by standard methods. Preliminary in vivo studies with 2Tc and 3Tc indicate low specific binding to folate receptors. In summary, Tc-99m folates 2Tc and 3Tc were prepared in high yields, using a one-pot transmetallation reaction with low soluble zinc dithiocarbamates (>1 ppm), at moderate temperature, without needing a subsequent purification step.

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46

Hasan, Md Sharif, Narhari Das, Zobaer Al Mahmud e S. M. Abdur Rahman. "Pharmacological Evaluation of Naproxen Metal Complexes on Antinociceptive, Anxiolytic, CNS Depressant, and Hypoglycemic Properties". Advances in Pharmacological Sciences 2016 (2016): 1–7. http://dx.doi.org/10.1155/2016/3040724.

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Purpose. The present study was designed to investigate the antinociceptive, anxiolytic, CNS depressant, and hypoglycemic effects of the naproxen metal complexes.Methods. The antinociceptive activity was evaluated by acetic acid-induced writhing method and radiant heat tail-flick method while anxiolytic activity was evaluated by elevated plus maze model. The CNS depressant activity of naproxen metal complexes was assessed using phenobarbitone-induced sleeping time test and the hypoglycemic test was performed using oral glucose tolerance test.Results. Metal complexes significantly (P<0.001) reduced the number of abdominal muscle contractions induced by 0.7% acetic acid solution in a dose dependent manner. At the dose of 25 mg/kg body weight p.o. copper, cobalt, and zinc complexes exhibited higher antinociceptive activity having 59.15%, 60.56%, and 57.75% of writhing inhibition, respectively, than the parent ligand naproxen (54.93%). In tail-flick test, at both doses of 25 and 50 mg/kg, the copper, cobalt, silver, and zinc complexes showed higher antinociceptive activity after 90 minutes than the parent drug naproxen. In elevated plus maze (EPM) model the cobalt and zinc complexes of naproxen showed significant anxiolytic effects in dose dependent manner, while the copper, cobalt, and zinc complexes showed significant CNS depressant and hypoglycemic activity.Conclusion. The present study demonstrated that copper, cobalt, and zinc complexes possess higher antinociceptive, anxiolytic, CNS depressant, and hypoglycemic properties than the parent ligand.

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Webb, Dylan, e J. Robin Fulton. "Utilising an anilido-imino ligand to stabilise zinc-phosphanide complexes: reactivity and fluorescent properties". Dalton Transactions 48, n.º 23 (2019): 8094–105. http://dx.doi.org/10.1039/c9dt00681h.

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Anilido-imino-based ligands have been used to generate new zinc complexes, including rare zinc phosphanide and phosphinodichalcogenoate complexes. The fluorescence intensity of these compounds is highly dependent upon the non-ancillary ligand.

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Kuriplach, Jan, Gerhard Brauer, Oksana Melikhova, Jakub Čížek, Ivan Procházka, W. Anwand e Wolfgang Skorupa. "Vacancy-Hydrogen Complexes in ZnO". Materials Science Forum 607 (novembro de 2008): 117–21. http://dx.doi.org/10.4028/www.scientific.net/msf.607.117.

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Hydrogen is an important impurity in zinc oxide and can be incorporated into the lattice in several ways. Hydrogen can be also bound by vacancies that can be studied using positron annihilation techniques. Here we examine theoretically oxygen and zinc vacancies in ZnO, the latter also with hydrogen atoms inside. Several computational approaches are employed to determine the defect geometries and related positron characteristics. Positron-induced forces are also taken into account. Calculated positron lifetimes are compared with those observed in experiment, which gives an indication of the presence of zinc vacancy-hydrogen complexes in ZnO materials.

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Xue, Ling-Wei, Xu Fu, Gan-Qing Zhao e Qing-Bin Li. "Zinc(II) Complexes Derived from Schiff Bases: Syntheses, Structures, and Biological Activity". Acta Chimica Slovenica 68, n.º 1 (20 de março de 2021): 17–24. http://dx.doi.org/10.17344/acsi.2020.5817.

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Three new zinc(II) complexes, [Zn2I2(L1)2] (1), [Zn(HL2)2(NCS)2] (2), and [ZnIL3] (3), where L1 is the anionic form of 2-[(6-methylpyridin-2-ylimino)methyl]phenol (HL1), HL2 is the zwitterionic form of 2-(cyclopropyliminomethyl)-5-fluorophenol (HL2), and L3 is the anionic form of 5-bromo-2-[(3-morpholin-4-ylpropylimino)methyl] phenol (HL3), have been prepared and characterized by elemental analyses, IR, UV and NMR spectra, and single crystal X-ray crystallographic determination. Complex 1 is a dinuclear zinc complex, and complexes 2 and 3 are mononuclear zinc complexes. The Zn atoms in the complexes are in tetrahedral coordination. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were evaluated.

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Takashima, Hiroshi, Daisuke Nakane e Takashiro Akitsu. "Application of Infrared Free-Electron Laser Irradiation of Protein Complexes Binding to Salen-Type Schiff Base Zn(II) Complexes Using Secondary Conformational Changes in the Proteins for the Treatment of Alzheimer’s Disease". Inorganics 12, n.º 2 (3 de fevereiro de 2024): 50. http://dx.doi.org/10.3390/inorganics12020050.

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Alzheimer’s disease causes the destruction of cranial nerve cells and is said to be caused by neuronal cell death due to the accumulation of amyloid-β protein. One method for the treatment of Alzheimer’s disease is to reduce the toxicity of the amyloid beta protein. Among the possibilities is to reduce toxicity by changing the secondary structure of the protein. In this study, the secondary structure of the protein was verified by binding a zinc complex to the protein and irradiating it with an infrared free-electron laser (IR-FEL). By binding Salen-Type zinc complexes to human serum albumin (HSA) and irradiating it with IR-FEL, structural changes were observed in the α-helix and β-sheet, the secondary structure of HSA. In addition to researching the possibility of binding zinc complexes to small proteins, docking simulations were examined. GOLD docking simulations showed that it is possible to bind zinc complexes to lysozyme (Lyz), a small protein. These results suggest that binding zinc complexes to amyloid-β and inducing a secondary conformational change through IR-FEL irradiation could be used for the treatment of Alzheimer’s disease by making the complexes lose their toxicity.

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