12,709 results on '"Chelates"'
Search Results
2. Bis‐Silylene‐Supported Aluminium Atoms with Aluminylene and Alane Character.
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Saddington, Artemis, Dong, Shicheng, Yao, Shenglai, Zhu, Jun, and Driess, Matthias
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IRON chelates , *LIGANDS (Chemistry) , *DENSITY functional theory , *ELECTRONIC structure , *ALUMINUM - Abstract
The suitability of electron‐rich bis‐silylenes, specifically the neutral chelating [SiII(Xant)SiII] ligand (SiII=PhC(NtBu)2Si, Xant=9,9‐dimethylxanthene) and the anionic [SiII(NAcrid)SiII)]− pincer ligand (NAcrid=2,7,9,9‐tetramethylacridane), has been successfully probed to stabilize monovalent bis‐silylene‐supported aluminium complexes (aluminylenes). At first, the unprecedented aluminium(III) iodide precursors [SiII(Xant)SiII]AlI2+ I−1 and [SiII(NAcrid)SiII)]AlI22 were synthesized using AlI3 and [SiII(Xant)SiII] or [SiII(NAcrid)SiII)]Li(OEt2)], respectively, and structurally characterized. While reduction of 1 with KC8 led merely to unidentified products, the dehalogenation of 2 afforded the dimer of the desired {[SiII(NAcrid)SiII)]Al:} aluminylene with a four‐membered SiIV2AlIII2 ring. Remarkably, the proposed aluminylene intermediates [SiII(Xant)SiII]AlII and {[SiII(NAcrid)SiII)]Al:} could be produced through reaction of 1 and 2 with Collman's reagent, K2Fe(CO)4, and trapped as AlI:→Fe(CO)4 complexes 5 and 6, respectively. While 6 is stable in solution, 5 loses one CO ligand in solution to afford the silylene‐ and aluminylene‐coordinated iron(0) complex 7 from an intramolecular substitution reaction. The electronic structures of the novel compounds were investigated by Density Functional Theory calculations. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Highly sulfonated poly ether ether ketone chelated with Cu2+ as a proton exchange membrane at sub-zero temperatures.
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Li, Xu, Qian, Libing, Zhang, Dongwei, Zhang, Haoliang, Yang, Lan, Song, Guoqing, Han, Jinzhao, Li, Jingjing, Chen, Zhiyuan, Fang, Pengfei, and He, Chunqing
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KETONES , *POLYETHERS , *PROTON conductivity , *DIFFERENTIAL scanning calorimetry , *COMPOSITE membranes (Chemistry) , *CHELATES - Abstract
[Display omitted] • Cu2+-chelated SPEEK membrane with high IEC is prepared. • High mechanical and dimensional stability are observed for SPEEK-Cu membrane. • Proton conductivity of SPEEK-based membranes reaches 0.074 S/cm at −25 °C. • Water states of samples at subzero temperatures are quantified via DSC analysis. • SPEEK-Cu membrane possesses a stronger anti-freezing property. Improving the proton conductivity (σ) of proton exchange membranes at low temperatures is very important for expanding their application areas. Here, sulfonated poly ether ether ketone (SPEEK) membranes were prepared with different sulfonation degrees, and its maximum ion exchange capacity is 3.15 mmol/g for 10 h at 60 °C. Highly sulfonated SPEEK membrane exhibits ultra-high water uptake and excellent proton conductivity of 0.074 S/cm at −25 °C due to its abundant −SO 3 H. Nevertheless, its high swelling ratio and low mechanical strength are not conducive to the practical application of the membrane. Luckily, by employing the chelation of Cu2+ with −SO 3 − on the SPEEK chain, Cu2+-coordinated SPEEK membranes were prepared, and they not only retain high −SO 3 H content but also possess robust mechanical properties and good dimensional stability compared to pristine SPEEK membrane. Meanwhile, the σ of the SPEEK-Cu membrane reaches 0.054 S/cm at −25 °C, and its fuel cell maximum power (W max) reaches 0.42 W/cm2 at −10 °C, demonstrating superior low-temperature performance in comparison to other reported materials. Particularly, water states in the prepared membranes are quantified by low-temperature differential scanning calorimetry. Because much more water bound to the plentiful −SO 3 H and Cu2+ inside the membrane endows it with anti-freezing performance, the decay of the σ and the W max for the SPEEK-Cu membrane is retarded at sub-zero temperatures. It is envisioned that composite membranes comprising metal ions such as Cu2+-SPEEK have a high potential for sub-zero fuel cell applications. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Palladium‐Catalyzed Regioselective C(4)−H Fluoroalkoxylation of Indoles Through Weak Chelation Assistance.
- Author
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Vijaykumar, Muniyappa, Gonnade, Rajesh G., and Punji, Benudhar
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FUNCTIONAL groups , *CHELATION , *INDOLE compounds , *PALLADIUM , *CHELATES - Abstract
Installing fluoroalkyl motifs into biorelevant indoles is particularly interesting due to their ubiquitous presence in drug molecules. Herein, we demonstrate the regioselective C4 fluoroalkoxylation of indoles using fluoroalcohols via palladium‐catalyzed chelation‐assisted C─H activation. The weak chelating benzoyl moiety at the C3 position acts as a directing group for remote C(4)─H fluoroalkoxylation of diversely substituted indoles. This methodology demonstrates a high level of regioselectivity and tolerates a range of crucial functional groups, yielding diverse trifluoroalkoxylated indoles in moderate to good yields. Removal of directing/protecting groups and further functionalization established the synthetic utility of the methodology. A preliminary mechanistic investigation is conducted by isolating the palladacycle intermediate and performing the deuterium scrambling study. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Synthesis, Structure, and Reactivity of Ruthenium‐Indane Complexes with Diphosphine Ligand.
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Itazaki, Masumi, Kitani, Natsumi, Dobashi, Yukako, Okabayashi, Kento, Nakazawa, Hiroshi, and Moriuchi, Toshiyuki
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LIGANDS (Chemistry) , *CATALYTIC activity , *CHELATES , *DIPHOSPHINE , *ELEMENTAL analysis - Abstract
Ruthenium‐indane complex, fac‐[Ru(NCMe)3(CO)2(InCl3)] 1Cl reacted with 0.5 equiv. of dppe/dppp to afford dinuclear ruthenium‐indane complexes linked by diphosphine ligand, [{Ru(NCMe)2(CO)2(InCl3)}2{μ2‐Ph2P(CH2)nPPh2}] (n=2: 3, 3: 4). On the other hand, the reaction of fac‐[Ru(NCMe)3(CO)2(InCl3)] 1Cl with 1 equiv. of dppp afforded the corresponding chelate ruthenium(0) indane complex, [Ru(NCMe)(CO)2(InCl3)(dppp)] 5. In the case of dppm, a chelate complex [Ru(NCMe)(CO)2(InCl3)(dppm)] 6 was formed via the dinuclear Ru complex [{Ru(NCMe)2(CO)2(InCl3)}2(μ2‐dppm)]. Complexes 1Cl, 5, and 6 showed a catalytic activity for double‐hydrosilylation of MeCN. Complexes 3–6 were fully characterized using NMR measurements, elemental analyses, and the structures of 1Cl, 3, 5, and 6 were determined by X‐ray crystallography. [ABSTRACT FROM AUTHOR]
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- 2024
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6. A Zr-hydroxamate metal–organic framework with intrinsic chelating sites for postsynthetic Pd metalation and Suzuki–Miyaura catalysis.
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Shao, Zhen-Wu, Xiong, Chaozhi, Yang, Jiajie, Mei, Zhewei, Xiong, Li, Wu, Wenjing, and Liu, Chong
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COORDINATE covalent bond , *HETEROGENEOUS catalysts , *METALATION , *CHELATES , *CATALYSIS - Abstract
A highly crystalline and robust Zr-hydroxamate metal–organic framework (MOF) was prepared from a pyrazine-based ligand, featuring abundant N,N′ chelating sites. High-degree Pd(II) metalation of the MOF was achieved through straightforward postsynthetic modification, with detailed coordination chemistry elucidated spectroscopically. The Pd-functionalized MOF was then studied as a heterogeneous Suzuki–Miyaura catalyst, through combined experimental/computational methods. [ABSTRACT FROM AUTHOR]
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- 2024
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7. The suprachelate effect: a pathway to supramolecules with Cu(II) and ethylenediamine.
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Lawler, Fenton C., Storteboom, Ryan S., Rosales-Lopez, Plinio D., Selvaggio, Katherine J., Zogg, Krista A., Chen, Trevina, Heule, Dafna L., Hoogstra, Madison N., Daspit, Orin R., Grabill, Magdalene A., Stonehouse, Adelaide A., Jipping, Anna E., Baker, Aerin E., and Vander Griend, Douglas A.
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BINDING constant , *SUPRAMOLECULES , *ETHYLENEDIAMINE , *CHELATES , *VOLUMETRIC analysis , *COPPER - Abstract
This paper portrays the solution-phase dynamics as copper(II) and ethylenediamine explore a multitude of different complexes. The data from five spectrophotometric titrations were globally analysed, evidencing four predominant species ([Cu]2+, [Cu(en-
N,N’ )]2+, [Cu(en-N,N’ )2]2+, [Cu(en-N )4]2+) along with their molar absorptivity curves and associative binding constants. The data also seem to support a fifth species, [Cu2(µ-en-N,N’ )]4+, in which ethylenediamine bridges two Cu(II) centres. The thermodynamic stability of all five species is corroborated byab initio computational calculations. The potential existence of [Cu(en-N )4]2+ highlights the suprachelate effect – going beyond the chelate effect – where multidenticity is overtaken by monodenticity. Such dangling multidentate ligands are available to bind to additional metal centres and thus build towards self-assembling supramolecules. [ABSTRACT FROM AUTHOR]- Published
- 2024
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8. Silver Complex Bearing N‐Heterocyclic Carbene Bidentate Chelating Ligand as an Efficient Catalyst in Solvent‐Free KA2 Coupling.
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Mateus, Miguel and Rycek, Lukas
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COUPLING reactions (Chemistry) , *SILVER , *CHELATES , *KETONES , *MOIETIES (Chemistry) - Abstract
We report a synthesis of silver complexes bearing chelating bidentate N‐heterocyclic carbene, with various substitutions at the terminal positions of the imidazole moiety of the NHC units. The long aliphatic substituents proved to be beneficial in terms of the synthetic efficiency of the complexes, compared to previously reported methyl substitution. The complexes demonstrated excellent suitability for the KA2 coupling reaction, providing quaternary carbon‐containing propargylic amines in yields up to 95 %, under solvent‐free conditions. The method showed high tolerance for a wide range of substrates, including naturally occurring ketones, underscoring its practicality. To our knowledge, this represents the first use of a well‐defined silver species in KA2 coupling, marking an advancement in the field. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Assessing the Impact of Amide Donor Groups on Stability and NMR Relaxation Efficiency of Monohydrated Fe(III) Complexes.
- Author
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Macchia, Maria Ludovica, Nucera, Alessandro, Ricci, Marco, Carniato, Fabio, Baranyai, Zsolt, and Botta, Mauro
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FOREIGN exchange rates , *CONTRAST media , *AMIDES , *CARBOXYL group , *CHELATES - Abstract
This study aims to understand the impact of the overall charge of Fe(III) chelates on their water exchange kinetics, thermodynamic stability, and kinetic inertia. To this end, we synthesized two CDTA‐amide ligands, each characterized by the replacement of one or two carboxyl groups with diethylamide functionalities. These alterations produced Fe(III) complexes with neutral or positively charged characteristics. The rate of water exchange (kex) was determined through a combined analysis of 1H relaxometric data and 1⁷O NMR chemical shift and transverse relaxation rate data. Additionally, we evaluated the thermodynamic stability and kinetic inertness of the complexes using potentiometry, UV‐Vis spectrophotometry, and capillary zone electrophoresis. Our results indicate that altering the charge of the complex slows down kex, consistent with previous observations for Gd(III) and Mn(II) chelates. Furthermore, the results indicate that incorporating amide donor groups decreases the stability of the complexes and reduces their kinetic inertia. However, both stability and kinetic inertia remain higher than those of [Fe(EDTA)]−. These findings provide some valuable insights for the development of Fe(III)‐based MRI probes alternative to those based on Gd(III). [ABSTRACT FROM AUTHOR]
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- 2024
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10. Severe Congenital Lead Poisoning in Siblings.
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Velagala, Suganthinie, Chhikara, Aditya, and Haile, Jennifer
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MISCARRIAGE , *LEAD poisoning , *EARLY medical intervention , *MOTHERS , *RARE diseases , *NEONATAL intensive care units , *HOSPITAL admission & discharge , *INTRAMUSCULAR injections , *SEVERITY of illness index , *PICA (Pathology) , *NEONATAL intensive care , *DEVELOPMENTAL disabilities , *LOW birth weight , *CHELATES , *LEAD , *DISEASE complications - Abstract
Congenital lead toxicity is rare. Lead freely crosses the placenta, therefore, placing the developing fetus at a higher risk for lead toxicity. This can lead to adverse consequences, such as spontaneous abortion, low birth weight, low IQ, and neurodevelopmental impairment. We present a rare case of siblings born to a mother with pica behaviors. Her venous lead level was 42 μg/dL at the time of disclosure. The repeat venous level at delivery 2 weeks later was 61 μg/dL. The infant's venous level shortly after birth was 89 μg/dL. The neonate was transferred to the NICU, where he received 9 doses of intramuscular dimercaprol and 5 days of intravenous Ca2Na2EDTA. Seventy-two hours after completing chelation, the blood lead level rebounded to 46 μg/dL. A 19-day course of dimercaptosuccinic acid was then initiated. As of 12 months of age, he has not required additional chelation. Shortly after, the mother conceived another child, who was born prematurely at 29 weeks. Twelve days before delivery, the mother's lead level was 30 ug/dL. The infant's lead level was 32 ug/dL at the time of delivery. The infant's lead trended down without requiring chelation. Both children have since demonstrated developmental delays and have needed early intervention services. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Boron‐Stereogenic Compounds: Synthetic Developments and Opportunities.
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Guo, Yonghong, Zu, Bing, Du Chen, Cadmus, and He, Chuan
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RESOLUTION (Chemistry) , *CHELATES , *ASYMMETRIC synthesis , *CHEMISTS , *CHIRALITY - Abstract
Comprehensive Summary: The 21st century has witnessed a continuous evolution in the development of boron‐stereogenic chemistry. Since the 1990s, various innovations for the synthesis of tetracoordinate boron‐stereogenic compounds, which exhibited great potential applications, have been demonstrated by synthetic chemists. This paper reviews the significant progress and recent advances towards the assembly of enantioenriched boron‐stereogenic compounds, and hopes to shed light on new perspectives and inspire further research in this emerging field. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Research Status of Peptide-Calcium Chelation and Absorption Mechanism.
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ZHANG Haotong, ZHOU Xuewei, QIAO Kaina, WU Huimin, YANG Rui, and ZHANG Yuyu
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CALCIUM supplements ,INTERMOLECULAR forces ,INTESTINAL absorption ,CHELATES ,BINDING sites - Abstract
Calcium is one of the essential macro-elements in the human body. The scientific calcium supplementation is greatly significant to maintaining life and health. The peptide-calcium chelates with good calcium binding capacity and high bioavailability have attracted more attention. This work reviews the binding sites, binding modes, and intermolecular forces between calcium and peptides in peptide-calcium chelates. Compared with free calcium, chelated calcium is more easily absorbed in the intestine according to the summarization of the calcium absorption pathways. Peptide-calcium chelates, as a new generation of calcium supplements, have a rich source of raw materials, high bioavailability, good economic value, and broad development prospects. Further research is needed on the safety, physicochemical stability, digestive stability, and Ca
2+ release mechanism of peptide-calcium chelates after intestinal absorption. This paper aims to provide new insight into the development of novel calcium supplements. [ABSTRACT FROM AUTHOR]- Published
- 2024
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13. Cationic ligands – from monodentate to pincer systems.
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Zafar, Mohammad, Subramaniyan, Vasudevan, Tibika, Françoise, and Tulchinsky, Yuri
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ELECTRONIC structure , *CHELATES , *OXIDATION-reduction reaction , *SPECIES - Abstract
For a long time, the small group of cationic ligands stood out as obscure systems within the general landscape of coordinative chemistry. However, this situation has started to change rapidly during the last decade, with more and more examples of metal-coordinated cationic species being reported. The growing interest in these systems is not only of purely academic nature, but also driven by accumulating evidence of their high catalytic utility. Overcoming the inherently poor coordinating ability of cationic species often required additional structural stabilization. In numerous cases this was realized by functionalizing them with a pair of chelating side-arms, effectively constructing a pincer-type scaffold. This comprehensive review aims to encompass all cationic ligands possessing such pincer architecture reported to date. Herein every cationic species that has ever been embedded in a pincer framework is described in terms of its electronic structure, followed by an in-depth discussion of its donor/acceptor properties, based on computational studies (DFT) and available experimental data (IR, NMR or CV). We then elaborate on how the positive charge of these ligands affects the spectroscopic and redox properties, as well as the reactivity, of their complexes, compared to those of the structurally related neutral ligands. Among other systems discussed, this review also surveys our own contribution to this field, namely, the introduction of sulfonium-based pincer ligands and their complexes, recently reported by our group. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Source-dependent effects of early-life zinc supplementation in milk on growth performance and starter intake of pre-weaned dairy calves.
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Rajaei-Sharifabadi, Hossein, Shamkhani, Esmaeil, Hafizi, Maryam, Mohammadi, Sajjad, Shokri, Zahra, Ahmadibonakdar, Yasaman, and Seradj, Ahmad Reza
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FEED analysis ,CHELATES ,ZINC sulfate ,INVESTIGATIONAL therapies ,CALVES - Abstract
This study aimed to evaluate the effects of milk supplementation with different zinc (Zn) sources on growth rate, starter intake, diarrhea incidence, and nutrient digestibility in dairy calves during the pre-weaning period. Forty newborn Holstein heifer calves were assigned to four treatments: control (no Zn supplementation; CON) or supplementation with 80 mg/day Zn from zinc sulfate (Zn-Sul), chelated zinc (Zn-Bon), or zinc methionine (Zn-Met). The Zn supplements were provided via milk from days 3 to 14 of age. Body weight (BW) and starter intake (SI) were monitored until weaning on day 70. Serum metabolite concentrations were determined in blood samples collected on days 15 and 70. Fecal consistency index (FCI) and frequency of medical treatments weremeasured during the first 21 days of life. Apparent total tract digestibility (ATTD) was determined in the 10th week of life. Although the effects of Zn supplementation on BWgain or body measurementswere non-significant, a tendency for treatment Ã-- time interaction on BW was observed, with variations among the experimental groups becoming more pronounced on days 56 and 70, showing higher values in Zn-supplemented calves compared to CON. SI was improved by Zn supplementation, with the greatest response in the Zn-Bon group. Compared to control, ATTD of organic matter, neutral detergent fiber, and starch tended to increase with Zn supplementation. Bloodmetabolites and FCI did not differ among the experimental treatments. Although no significant difference was detected between Zn-Met and CON, the frequency of medical treatment was significantly lower in Zn-Bon and Zn-Sul compared to CON calves. In conclusion, zinc supplementation in milk, particularly with the organic chelated zinc source (Zn-Bon), showed promising effects on increasing starter intake and reducing medical treatments, along with trends toward enhanced growth and nutrient digestibility in pre-weaned calves. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Synthesis and Antitumor Activity of Photosensitizer Eugenol Porphyrin Derivatives: A Combination Therapy of Chemotherapy and Photodynamic Therapy.
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Li, Hui, Tang, Chen, Liu, Zhenhua, Tian, Zejie, Shi, Lei, Yang, Lingyan, He, Jun, Ai, Wenbin, He, Xufeng, and Liu, Yunmei
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PHOTODYNAMIC therapy , *CHELATES , *PHOTOSENSITIZERS , *METAL compounds , *ANTINEOPLASTIC agents , *REACTIVE oxygen species - Abstract
ABSTRACT Photodynamic therapy (PDT) is a promising treatment for cancer. At present, the development of photosensitizers has become a hot spot for research at home and abroad. In this study, 20 porphyrin‐butylphenol compounds were synthesized, and the structures of the target compounds were analyzed by means of 1H NMR, IR, mass spectrometry, and other analytical methods. The quantum yield of the target compound as a photosensitizer for the production of singlet oxygen was determined by using a DPBF reactive oxygen probe (1,3‐diphenylisobenzofuran). The anticancer activity of the synthesized target compounds was studied using HepG2 cells and A549 cells. The results of the singlet oxygen experiments showed that the Zn metal chelated compound had better singlet oxygen production than the free‐base porphyrin. The cellular activity assays showed that the metal‐chelated compounds exhibited better in vitro antitumor activity. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Evaluation of survivorship and annulus validation in calcein-stained freshwater unionid mussels.
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Eismont, Anna L., deMoulpied, Michael, Robertson, Clinton R., Lopez, Roel R., and Randklev, Charles R.
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FRESHWATER mussels , *ULTRAVIOLET radiation , *MUSSELS , *CHELATES - Abstract
Unionid mussels deposit growth rings (annuli) within the shell, which can be used to estimate age and growth. Thin-sectioning is a common technique for counting annuli, wherein a cross-section of a shell valve is taken and evaluated by multiple readers. Correctly identifying annuli can be challenging because ambiguous annuli can bias growth estimates. Staining with calcein, a fluorescent chemical, is a technique that has been used with marine and freshwater species to improve accuracy of growth estimates. This method chelates calcium, causing a permanent mark that fluoresces under ultraviolet light. Calcein has seen limited testing on unionid mussels so it remains unclear if this method has adverse effects on survival and growth. We evaluated calcein against 2 concentrations (125 mg L−1 and 250 mg L−1) at 2 exposure times (12 and 24 h) on Cyclonaias pustulosa, a common North American unionid. Survivorship remained above 80% 6 months post-immersion. Mark quality and retention for 250 mg L−1 were high for both 12- and 24-h immersions, although historical annuli were not highlighted. These findings corroborate studies indicating calcein immersion is generally safe and effective in juveniles and adults and suggest it may be useful in validating new growth. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Amphetamine-like Deferiprone and Clioquinol Derivatives as Iron Chelating Agents.
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El Safadi, Mahmoud, Wilson, Katie A., Strudwicke, Indigo J., O'Mara, Megan L., Bhadbhade, Mohan, Rawling, Tristan, and McDonagh, Andrew M.
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CHELATES , *IRON chelates , *PARKINSON'S disease , *MOLECULAR dynamics , *AQUEOUS solutions , *DOPAMINE receptors , *CHELATING agents - Abstract
The accumulation of iron in dopaminergic neurons can cause oxidative stress and dopaminergic neuron degeneration. Iron chelation therapy may reduce dopaminergic neurodegeneration, but chelators should be targeted towards dopaminergic cells. In this work, two series of compounds based on 8-hydroxyquinoline and deferiprone, iron chelators that have amphetamine-like structures, have been designed, synthesized and characterized. Each of these compounds chelated iron ions in aqueous solution. The hydroxyquinoline-based compounds exhibited stronger iron-binding constants than those of the deferiprone derivatives. The hydroxyquinoline-based compounds also exhibited greater free radical scavenging activities compared to the deferiprone derivatives. Molecular dynamics simulations showed that the hydroxyquinoline-based compounds generally bound well within human dopamine transporter cavities. Thus, these compounds are excellent candidates for future exploration as drugs against diseases that are affected by iron-induced dopaminergic neuron damage, such as Parkinson's disease. [ABSTRACT FROM AUTHOR]
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- 2024
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18. Copper(II) Methacrylate Complexes with Imidazole Derivatives—Structural, Spectral and Antitumor Features.
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Teodoru, Dragoș Vlad, Olar, Rodica, Maxim, Cătălin, Bacalum, Mihaela, Răileanu, Mina, Iorgulescu, Emilia-Elena, Vasile Scăețeanu, Gina, and Badea, Mihaela
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MONOCLINIC crystal system , *FOURIER transform infrared spectroscopy , *CHELATES , *STEREOCHEMISTRY , *COPPER crystals - Abstract
A series of five novel copper(II) complexes with imidazole derivatives having general core Cu(R-Im)2(Macr)2 (Macr = methacrylate anion; R-Im = 2-methylimidazole/2-MeIm, 4-methylimidazole/4-MeIm, 2-ethylimidazole/2-EtIm, 2-isopropylimidazole/2-iPrIm) has been synthesized and characterized by elemental analysis, Fourier Transform Infrared spectroscopy (FTIR), electronic reflectance spectroscopy, cyclic voltammetry, thermal analysis and single crystal X-ray diffraction. All complexes crystalize in a monoclinic crystal system and form a complex supramolecular network developed through hydrogen bonds. The stereochemistry of the copper ion is distorted octahedral except for the compound with 4-methylimidazole for which the geometry is square-pyramidal. The imidazole derivatives act as unidentate while methacrylate ions are chelated except for compound with 4-methylimidazole where is unidentate. All ligands and complexes inhibited B16 murine melanoma cells in a micromolar range, but the complex with 2-isopropylimidazole was more active. Furthermore, all species do not affect the healthy BJ cells in the concentration range used for assays. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Preparation, physicochemical, anticancer, and theoretical studies of mono‐ and bi‐nuclear Ni(II), Co(II), and Cd(II) complexes containing chromone moiety.
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Shebl, Magdy, Adly, Omima M. I., Abdelrhman, Ebtesam M., and El‐Shetary, Basheir
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MOLAR conductivity , *DENSITY functional theory , *SCHIFF bases , *MOLECULAR docking , *CHELATES - Abstract
Reactions of a chromone‐based hydrazone (SalHFC; HL) with Ni(II), Co(II), and Cd(II) ions yielded new solid chelates with the general formula [M(L)X].nZ, M = Ni(II), Co(II) and Cd(II), X = NO3− or OAc−, n = 0.5–2, Z = H2O or EtOH for complexes 1, 3, 4, 6, 7, 8 and [M2(L)(OAc)3X].0.5EtOH.nH2O, M = Ni(II) and Co(II), X = H2O or EtOH, n = 1 or zero for complexes 2 and 5. The synthesized chelates have been successfully characterized by means of different analytical and spectroscopic tools. SalHFC performs as a monoanionic tridentate in all chelates except chelate 2 and 5 (monoanionic tetradentate). Molar conductivity measurements demonstrated a non‐electrolytic manner of all chelates. Nickel(II) and cobalt(II)‐SalHFC chelates displayed tetrahedral geometries whereas cadmium(II) chelates (7 and 8) were octahedral. TG was employed to inspect the thermal degradation patterns of SalHFC‐complexes, and the Coats‐Redfern equations were employed to estimate the kinetic parameters of the thermal degradation steps. Density functional theory (DFT) level implementation in the Gaussian 09 program at B3LYP/6‐311G(d,p) level was efficaciously used to predict the molecular structural properties of SalHFC and its chelates and the theoretical data and experimental findings were then integrated. SalHFC and its chelates displayed anticancer action against the HepG2 cell line and the results were verified by molecular docking studies. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Anti-corrosive agents based benzil-thiocarbohydrazone macrocyclic ligand-derived Cu (II) and Zn (II) chelates: template synthesis and physically admixing with epoxy coating.
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Elgammal, Walid E., Eliwa, Essam M., Goomaa, Hosni A., Owda, Medhat E., and Abd El-Wahab, H.
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COPPER , *EPOXY coatings , *THERMOGRAVIMETRY , *PAINT materials , *SCANNING electron microscopes , *CHELATES - Abstract
Purpose: This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating application. Design/methodology/approach: A selected macrocyclic Cu(II) and Zn(II) complexes were prepared via template synthesis and characterized using Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope, flexibility, hardness and adhesion of coating films prepared using epoxy paint. Findings: The corrosion resistance of the epoxy-painted films was improved due to the incorporation of the Zn and Cu complexes into the formulation. Originality/value: It was found that the metal complex-based formulation with Cu(II) and Zn(II) had outperformed the sample blank. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Usage of Chelating Gels in Root Canal Preparation: A Survey of Australian Clinicians.
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Wright, Patricia P., Diamond, Elise S., and Peters, Ove A.
- Subjects
CHI-squared test ,DENTAL pulp cavities ,CHELATION ,ENDODONTISTS ,CHELATES - Abstract
Chelating gels may initially assist in root canal preparations to help establish a glide path. While irrigation surveys have investigated liquid chelators and gels to a minor extent, no endodontic survey has focused on EDTA gels and why clinicians use them. All 395 members of the Australian Society of Endodontology (ASE) were emailed an 11-question survey concerning chelation gel usage via Qualtrics. Paper copies were also distributed at ASE events. Descriptive statistics were performed for practitioner and chelating gel data. Cross-tabulations of the practitioner type with the case percentage usage of gels were analyzed with the chi square test (adjusted p value < 0.0083). The overall response rate was 181/395 (46%). For 174 eligible responses, those who never/rarely used a gel were as follows: endodontic residents 12/14 (86%), endodontists 53/71 (75%), general dentists 39/86 (45%), and other members 0% (0/3). Most gel users said that gels helped establish a glide path. Those who never/rarely used chelating gels commented that they held no benefits over liquid EDTA. Endodontists were less likely to use a chelation gel than general dentists (p < 0.0083). Older clinicians had higher gel usage than younger ASE members (p < 0.0083), indicating a possible trend to diminished gel usage over time amongst ASE members. In conclusion, most ASE members find no need for a chelating gel, raising questions about their clinical effectiveness. Studies would therefore be warranted to investigate gel efficacy and improved clinical outcomes. [ABSTRACT FROM AUTHOR]
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- 2024
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22. Optimization of the Preparation Process and Ameliorative Efficacy in Osteoporotic Rats of Peptide–Calcium Chelates from Skipjack Tuna (Katsuwonus pelamis) Meat.
- Author
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Yan, Wan-Zhen, Wang, Jiao, Wang, Yu-Mei, Zeng, Yu-Hui, Chi, Chang-Feng, and Wang, Bin
- Subjects
SKIPJACK tuna ,LABORATORY rats ,BONE remodeling ,BONE growth ,CHELATES ,BONE resorption - Abstract
This study aimed to establish the preparation process of peptide–calcium chelates (TMP-Ca) using skipjack tuna meat and investigate the function and mechanism of TMP-Ca in an osteoporosis model of rats. The results indicated that trypsin is more suitable for preparing the Ca-chelating hydrolysates of tuna meat, and the optimal hydrolysis conditions were derived as follows: digestion time 4 h, material–liquid ratio 1:10, and enzyme dose 3%. The conditions for chelating Ca with tuna meat hydrolysate were optimized to be chelation time 50 min, temperature 50 °C, pH 8.0, and a peptide–Ca ratio 1:10. The prepared hydrolysate was subjected to ultrafiltration, and the fraction (TMP) (MW <1 kDa) showed the highest Ca chelation rate (51.27 ± 1.42%) and was made into the peptide–Ca chelates (TMP-Ca). In osteoporotic rats, TMP-Ca significantly improved the decrease in ovarian indexes caused by retinoic acid. It also elevated serum Ca, phosphorus, and bone turnover indexes, increased the number of bone trabeculae, and improved bone microstructure. In addition, we confirmed that TMP-Ca could regulate the OPG/TRAF6 pathway to reduce osteoclast differentiation, inhibit bone resorption, and promote bone formation. Therefore, TMP-Ca could significantly ameliorate osteoporosis, and this study provides a functional component for the preparation of healthcare products using skipjack tuna meat to treat osteoporosis. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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23. Lithium Tris(Oxalato)Aaluminate and its Hydrates: Structure, Dehydration and Thermal Decomposition.
- Author
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Missyul, Alexander, Kreuzer, Martin, Usoltsev, Oleg, Arsentev, Maxim, and Chislov, Mikhail
- Subjects
- *
OXALATES , *DEHYDRATION , *THERMAL expansion , *BRIDGING ligands , *CRYSTAL structure - Abstract
The double oxalates MI3[MIII(C2O4)3] possess rich crystallochemistry and can be used as precursors for various ceramic materials. The article discusses a case of Li3[Al(C2O4)3]. A series of previously unknown hydrates (Li3[Al(C2O4)3] ⋅ 5.5H2O, Li3[Al(C2O4)3] ⋅ 4H2O, Li3[Al(C2O4)3] ⋅ H2O) was found for this composition, their crystal structure and temperatures of mutual transformations determined. Transformation from Li3[Al(C2O4)3] ⋅ 4H2O to Li3[Al(C2O4)3] ⋅ H2O was found to be accompanied by a change in the topology of the bonding network. Uniaxial negative thermal expansion was found for anhydrous Li3[Al(C2O4)3]. Thermal decomposition of Li3[Al(C2O4)3] was demonstrated to be a promising way to obtain precursors for aluminate ceramics. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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24. Mausolates: Large‐Cavity Chelates with Potential as Delivery Vehicles in Nuclear Medicine.
- Author
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Ackroyd, Amanda J., Gajecki, Leah, Gogoulis, Athan T., Smart, Jack F., Oliver, Allen G., McIndoe, J. Scott, and Berg, David J.
- Subjects
- *
LIGANDS (Chemistry) , *NUCLEAR medicine , *METAL complexes , *THERMAL stability , *CHELATES - Abstract
A new type of diborate clathrochelate (cage) ligand featuring nine inwardly pointing nitrogen donors that form a large, rigid cavity, termed a mausolate, is presented. The cavity size and high denticity make this an attractive delivery vehicle for large radionuclides in nuclear medicine. Metal mausolate complexes are stable to air and water (neutral pH) and display extremely high thermal stability (>400 °C). Lanthanide uptake by the mausolate ligand occurs rapidly in solution at room temperature and once complexed, the lanthanide ions are not displaced by a 250‐fold excess of a competitive lanthanide salt over more than one week. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Synthesis, characterization, in vitro and in silico biological studies of 3d transition metal(II) chelates of a Schiff base derived from sulfamethazine and 3,5-diiodosalicylaldehyde.
- Author
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Saeed, Muhammad, Parveen, Bushra, Rasool, Nasir, Ghulam Ali, Kulsoom, and Munawar, Khurram Shahzad
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LIGANDS (Chemistry) , *METAL complexes , *CHELATES , *ASPERGILLUS niger , *ENTEROCOCCUS faecalis - Abstract
A Schiff base (imine) ligand, (E)-4-((2-hydroxy-3,5-diiodobenzylidene)amino)-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (HL), was synthesized by condensation of 3,5-diiodosalicylaldehyde with sulfamethazine. The ligand was then complexed with Zn(II), Cu(II), Ni(II), Co(II) and Fe(II) employing a metal to ligand ratio of 1:2 to form chelates (1-5), [M(L)2(H2O)2]. Characterization was done by UV-visible, FTIR, 1H and 13C NMR spectroscopy, elemental analysis, magnetic moments, thermogravimetric analyses (TGA) and conductance studies. The Schiff base behaved as a bidentate ligand and metal chelates assumed octahedral geometry. MOE-docking was employed to assess binding of the Schiff base (HL) and its chelates (1-5) with 1T2P, 1VVQ, 2W61, 3U2D, 4H8E and 5K18 proteins. Results indicated that Zn(II) chelate (1) and Fe(II) chelate (5) are the most potent compounds. Antibacterial and antibiofilm activities were executed against Enterococcus faecalis, Staphylococcus aureus, Proteus mirabilis and Klebsiella pneumoniae. Antifungal activities were performed against Candida albicans and Aspergillus niger. The Schiff base exhibited moderate antibacterial/antifungal activities that were enhanced on chelation with metal ions. Zinc(II) chelate (1) and Fe(II) chelate (5) show excellent antibacterial/antifungal activities. Complex 2 exhibited good antibiofilm activity. [ABSTRACT FROM AUTHOR]
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- 2024
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26. New europium complexes of C(6)-DTTA-appended 5-aryl-2,2′-bipyridines: synthesis, luminescence, and evaluation of their activity against cell culture.
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Krinochkin, A. P., Kopchuk, D. S., Valieva, M. I., Starnovskaya, E. S., Shtaitz, Ya. K., Kim, G. A., Slovesnova, N. V., Minin, A. S., Belousova, A. V., Pozdina, V. A., Kovalev, I. S., Zyryanov, G. V., Tsmokalyuk, A. N., Nikonov, I. L., and Rusinov, V. L.
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CHEMICAL synthesis , *CELL culture , *LUMINESCENCE , *EUROPIUM , *CHELATES , *REACTIVE oxygen species - Abstract
New 5-[4(3)-R-phenyl]-2,2′-bipyridines bearing the 1,1,7,7-tetrakis(tert-butoxycarbonylmethyl)-1,4,7-triazaheptane (DTTA) moiety at the C(6) position (R = Cl, Br, CF3) and their water-soluble EuIII complexes were synthesized. The photophysical properties of the synthesized complexes were investigated. More efficient sensitization of Eu3+ cation luminescence was demonstrated for a number of halogen-containing ligands. Some chelates exhibited moderate cell-staining ability. The synthesized compounds did not show significant photodynamic activity, which may be due to the inhibition of the in situ generation of reactive oxygen species via the supposed interaction with the methylene moiety of DTTA-appended 2,2′-bipyridine ligands. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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27. Thionitrosyl Complexes of Rhenium and Technetium with PPh 3 and Chelating Ligands—Synthesis and Reactivity.
- Author
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Nowak, Domenik, Hagenbach, Adelheid, Sawallisch, Till Erik, and Abram, Ulrich
- Subjects
- *
NITROSYL compounds , *TECHNETIUM , *RHENIUM , *CHEMICAL kinetics , *ELECTRON paramagnetic resonance spectroscopy , *CHELATES - Abstract
In contrast to corresponding nitrosyl compounds, thionitrosyl complexes of rhenium and technetium are rare. Synthetic access to the thionitrosyl core is possible by two main approaches: (i) the treatment of corresponding nitrido complexes with S2Cl2 and (ii) by reaction of halide complexes with trithiazyl chloride. The first synthetic route was applied for the synthesis of novel rhenium and technetium thionitrosyls with the metals in their oxidation states "+1" and "+2". [MVNCl2(PPh3)2], [MVNCl(PPh3)(LOMe)] and [MVINCl2(LOMe)] (M = Re, Tc; {LOMe}− = (η5-cyclopentadienyl)tris(dimethyl phosphito-P)cobaltate(III)) complexes have been used as starting materials for the synthesis of [ReII(NS)Cl3(PPh3)2] (1), [ReII(NS)Cl3(PPh3)(OPPh3)] (2), [ReII(NS)Cl(PPh3)(LOMe)]+ (4a), [ReII(NS)Cl2(LOMe)] (5a), [TcII(NS)Cl(PPh3)(LOMe)]+ (4b) and [TcII(NS)Cl2(LOMe)] (5b). The triphenylphosphine complex 1 is partially suitable as a precursor for ongoing ligand exchange reactions and has been used for the synthesis of [ReI(NS)(PPh3)(Et2btu)2] (3a) (HEt2btu = N,N-diethyl-N′-benzoyl thiourea) containing two chelating benzoyl thioureato ligands. The novel compounds have been isolated in crystalline form and studied by X-ray diffraction and spectroscopic methods including IR, NMR and EPR spectroscopy and (where possible) mass spectrometry. A comparison of structurally related rhenium and technetium complexes allows for conclusions about similarities and differences in stability, reaction kinetics and redox behavior between these 4d and 5d transition metals. [ABSTRACT FROM AUTHOR]
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- 2024
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28. X‐ray crystallographic of a novel pyrimidine ligand (LPH) and its metal chelates Cr3+, Ni2+, and Ru3+: A comprehensive study on synthesis, characterization, computational investigations, and biological evaluation toward anticancer and antioxidant
- Author
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Al‐Assy, Waleed H., Mostafa, Mohsen M., Smith, Stacey J., Harrison, Roger, Youssef, Magdy M., and Hassan, Eman A.
- Subjects
- *
LIGANDS (Chemistry) , *CHELATES , *PYRIMIDINES , *METALS , *ATOMS , *RUTHENIUM compounds , *X-rays - Abstract
2,4,6‐Triamino‐N‐phenylpyrimidine‐5‐carbothioamide (LPH) was synthesized and extensively characterized. Single crystal X‐ray confirms a monoclinic P21/c space group for LPH. The novel ligand and its chelates of Cr3+, Ni2+, and Ru3+ were studied by elemental analyses, spectral (13C‐,1H‐NMR, UV–visible, IR), magnetic, and thermal measurements. IR spectra indicated that LPH behaves in a bidentate mode through the two NH2 groups of the pyrimidine ring and/or a tetradentate coordination involving the nitrogen atoms of the two NH2 of the pyrimidine ring, NH, and the thioketo (C=S) groups, respectively. By utilizing the Gaussian 09 W program in DFT/B3LYP, we are able to conduct computational estimates of LPH and its metal chelates, yielding insightful data regarding their electronic structure and stability. Biological studies were conducted to assess the isolated compounds' activities against anticancer (MCF‐7), antioxidant (DPPH and ABTS), DNA, and antimicrobial proteins. Molecular docking was employed to investigate the chelates' inhibitory properties, specifically their binding propensity with MCF‐7 cells, revealing possible anticancer action. All the data help to understand LPH and its complexes' production, biological characteristics, and possible therapeutic uses. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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29. Spectral Characterization, Antioxidant, Antibacterial Activity, and Molecular Dynamics Simulation of a New Bis-benzimidazole Molecule, 1,5-Bis(1H-benzimidazol-2-yl)pentan-3-one.
- Author
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Karakurt, T., Tavman, A., Şahin, O., Çolak, D. N., and Karaçelik, A. A.
- Subjects
- *
OXIDANT status , *MOLECULAR dynamics , *PROTEIN-ligand interactions , *CHELATES , *FREE radicals - Abstract
Objective: Bis-benzimidazoles are an interesting class of compounds due to their chelating characteristics, various biological effects, and fluorescence properties. Methods: In this research, a new symmetric bis-benzimidazole derivative including a ketone group, 1,5-bis(1H-benzimidazol-2-yl)pentan-3-one (PBB), was synthesized and characterized. Antibacterial activity of PBB was tested against Gram-negative and Gram-positive bacteria. The total antioxidant capacity (as TEAC value) and free radical scavenging activity of (PBB) was determined by ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) methods. Molecular modeling methods have been conducted in order to study the relationship between electronic characteristics and antioxidant activity. Results and Discussion: Molecular modelling techniques and approaches were used to ensure that (PBB) synthesized in this study could be a reliable drug-like ligand, ligand-protein interactions were studied in detail with molecular dynamic (MD) simulation techniques applied at the molecular level, and trajectory analyses after MD were discussed. The total antioxidant capacity (as TEAC value) and free radical scavenging activity results revealed that (PBB) has a moderate inhibition with a SC50 = 1.8686 ± 0.0030 mg/mL value and the FRAP value is 108.89 ± 1.92 μM TEAC. Conclusions: According to the molecular modelling calculations, the antioxidant and antibacterial activities of (PBB) result from the electrophilic and nucleophilic interactions of its electron-rich C=N nitrogen atoms and electron-withdrawing carbon atoms adjacent to the C=O group with the proteins of the target molecules. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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30. Efficiency of chelated fertilizers in sunflower cultivation
- Author
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M. S. Sidakova
- Subjects
sunflower ,soil ,chelates ,organomics ,fertilizers ,yield ,efficiency ,quality ,Technology - Abstract
The article investigates the effect of innovative forms of fertilizers containing a full set of macro and microelements on the condition of plants, yield and quality of sunflower seeds in the foothills of the Kabardino-Balkarian Republic. ORGANOMIX brand M for oilseeds has a fungicidal effect and, having an immunity inducer and growth stimulator in its composition, promotes plant growth and the formation of seed tissues, an increase in overall yield, the accumulation of fat in seeds, and an improvement in the quality indicators of sunflower seeds. The article presents average data for the period 2021-2023. Sunflower has high requirements for the provision of soil with nutrients and is especially sensitive to boron deficiency. Double non-root treatment of sunflower plants in the phase of 2-3 and 4-6 pairs of true leaves with liquid chelated fertilizer ORGANOMIX oilseed, enhanced with the microelement BOR, has made it possible to obtain the highest yield under the experimental conditions - 26.4 c / ha of sunflower seeds. The quality of sunflower seeds plays a major role for agricultural producers. The fat content of seeds is the main quality characteristic and it depends on the husk content, which is determined by hereditary characteristics and the external environment has little effect on it. In our experiment, the highest oil content was obtained in the variant of using the ORGANOMIX oil fertilizer, enhanced with microelements BOR and ZINC in a mixture with ORGANOSTIM - 47.0%, the husk content varied from 24.5 to 25.9%.
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- 2024
- Full Text
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31. 2024 Product Directory List.
- Subjects
CONSTRUCTION industry ,MICRONUTRIENTS ,CHELATES ,DIRECTORIES ,NUTRITION - Published
- 2024
32. Five‐ or six‐membered aluminum metallocyclic complexes containing N, N bidentate oxazolinyl‐indolate chelate ring: Synthesis, structural, and catalytic studies.
- Author
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Chung, Hao‐Yu, Li, Cian‐Fu, Chen, Ming‐Tsz, and Chen, Chi‐Tien
- Subjects
- *
ALUMINUM compounds , *FUNCTIONAL groups , *ALUMINUM , *CHELATES , *ETHANES - Abstract
Treatment of two classes of oxazolinyl‐indolate ligand precursors with an equivalent trimethylaluminum reagent afforded four corresponding aluminum dimethyl complexes. Intramolecular functional groups were employed to switch coordination behaviors, resulting in the formation of two classes of five‐ or six‐membered aluminum metallocyclic complexes. The screening of the prepared aluminum complexes, mediated by 9‐anthracenemethanol as the initiating reagent in the ring‐opening polymerization of ε‐caprolactone, showed significant activities at room temperature. The aluminum compound ligated by 2‐(1H‐indol‐2‐yl)‐4,4‐dimethyl‐4,5‐dihydrooxazole possessed a suitable chelated ring size, and its intrinsic electronic properties maintained higher activity. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Novel heteroleptic copper(I) complexes merging the chelating 1,2-bis-diphenyldiphosphine and various L^X type coligands.
- Author
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Moussa, J. and Gontard, G.
- Subjects
- *
COPPER , *CHELATES , *LIGANDS (Chemistry) , *ULTRAVIOLET-visible spectroscopy , *X-ray diffraction , *COPPER compounds - Abstract
Three novel heteroleptic mononuclear copper(I) complexes with a chelating diphosphine 1,2-bis-diphenylphosphinobenzene ligand (dppb) and various monoanionic bidentate LX-type ligand derivatives, 2-methyl-8-hydroxyquinolinate (Me-Q), 6-methyl-2-picolinate (Me-Pic) and 2-(2′-pyridyl)benzimidazolate (pbim), were prepared. The complexes are of formulae [Cu(Me-Pic)(dppb)] (3), [Cu(Me-Q)(dppb)] (2) and [Cu(pbim)(dppb)] (4). The structures of two of the compounds were unambiguously confirmed by a complete single-crystal X-ray diffraction study. The complexes were also characterized by UV-Vis spectroscopy. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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34. Ligand Basicity and Chelate Effects on Sulfur Insertion vs. Sulfur Reduction by Zinc Thiolate Complexes.
- Author
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Seo, W. T. Michael, Tsang, Victor A., Ballesteros, Moises, and Tsui, Emily Y.
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ZINC compounds , *SULFUR , *CHELATES , *BASICITY , *INORGANIC chemistry , *LIGANDS (Chemistry) - Abstract
4‐ and 5‐coordinate zinc thiolate complexes supported either by bis(carboxamide)pyridine frameworks or by substituted tris(pyrazolyl)borate ligands react with elemental sulfur (S8) following two distinct pathways. Some zinc thiolate moieties insert sulfur atoms to form zinc polysulfanide complexes, while others reduce sulfur and oxidize the thiolate. Here, we compare the effects of ligand electronics, strain, and sterics for selecting the respective reaction pathway. These results show that chelating and electron‐deficient thiolate ligands better stabilize persistent zinc‐bound polysulfanide species. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
35. Ir(III) Metal Emitters with Cyano‐Modified Imidazo[4,5‐b]pyridin‐2‐ylidene Chelates for Deep‐Blue Organic Light‐Emitting Diodes.
- Author
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Wu, Yixin, Xin, Yangyang, Pan, Yi, Yiu, Shek‐Man, Yan, Jie, Lau, Kai Chung, Duan, Lian, and Chi, Yun
- Subjects
- *
LIGHT emitting diodes , *CHELATES , *QUANTUM efficiency , *METALS , *PHOSPHORS - Abstract
Ir(III) carbene complexes have been explored as one of the best blue phosphors for their high performance. Herein, the authors designed and synthesized a series of blue‐emitting Ir(III) phosphors (f‐ct9a–c), featuring fac‐coordinated cyano‐imidazo[4,5‐b]pyridin‐2‐ylidene cyclometalates. These Ir(III) complexes exhibit true‐blue emission with a peak maximum spanning 448–467 nm, with high photoluminescence quantum yields of 81–88% recorded in degassed toluene. Moreover, OLED devices bearing phosphors f‐ct9a and f‐ct9b deliver maximum external quantum efficiencies (EQEmax) of 25.9% and 30.3%, together with Commission Internationale de L'Eclairage (CIEx,y) coordinates of (0.157, 0.225) and (0.142, 0.169), respectively. Remarkably, the f‐ct9b‐based device displays an incredible EQE of 29.0% at 5000 cd·m−2. The hyper‐OLED device based on f‐ct9b and ν‐DABNA exhibits an EQEmax of 34.7% and CIEx,y coordinates of (0.122, 0.131), affirming high potentials in achieving efficient blue electroluminescence. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Prodrug-inspired adenosine triphosphate-activatable celastrol-Fe(III) chelate for cancer therapy.
- Author
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Hanrong Li, Yifan Li, Lingpu Zhang, Nan Wang, Dong Lu, Dongsheng Tang, Yitong Lv, Jinbo Zhang, Heben Yan, He Gong, Ming Zhang, Kaili Nie, Yi Hou, Yingjie Yu, Haihua Xiao, and Chaoyong Liu
- Subjects
- *
CANCER treatment , *CHELATES , *REACTIVE oxygen species , *STRUCTURAL stability , *TUMOR microenvironment - Abstract
Celastrol (CEL), an active compound isolated from the root of Tripterygium wilfordii, exhibits broad anticancer activities. However, its poor stability, narrow therapeutic window and numerous adverse effects limit its applications in vivo. In this study, an adenosine triphosphate (ATP) activatable CEL-Fe(III) chelate was designed, synthesized, and then encapsulated with a reactive oxygen species (ROS)-responsive polymer to obtain CEL-Fe nanoparticles (CEL-Fe NPs). In normal tissues, CEL-Fe NPs maintain structural stability and exhibit reduced systemic toxicity, while at the tumor site, an ATP-ROS-rich tumor microenvironment, drug release is triggered by ROS, and antitumor potency is restored by competitive binding of ATP. This intelligent CEL delivery system improves the biosafety and bioavailability of CEL for cancer therapy. Such a CEL-metal chelate strategy not only mitigates the challenges associated with CEL but also opens avenues for the generation of CEL derivatives, thereby expanding the therapeutic potential of CEL in clinical setting. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Reduction of (pddi)Cr reveals redox noninnocence via C–C bond formation amidst competing electrophilicity: [(cpta)CrMen]− (n = 0, 1) and [(pta)Cr]−.
- Author
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D'Arpino, Alexander A., Wolczanski, Peter T., MacMillan, Samantha N., Cundari, Thomas R., and Krumov, Mihail R.
- Subjects
- *
OXIDATION-reduction reaction , *CYCLOPROPANE , *CHELATES , *ANIONS - Abstract
Reversible cyclopropane formation is probed as a means of redox noninnocence in diimine/diamide chelates via reduction and complex anion formation. Competition from imine attack renders complications in the latter approach, and electrochemical measurements with calculational support provide the rationale. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Light-induced spin-state switching in Fe(II) spin-crossover complexes with thiazole-based chelating ligands.
- Author
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Jo, Minyoung, Amanyazova, Botagoz, Yergeshbayeva, Sandugash, Gakiya-Teruya, Miguel, Üngör, Ökten, Lopez Rivera, Paola, Jen, Natalie, Lukyanenko, Evgeny, Kurkin, Alexander V., Erkasov, Rakhmetulla, Meisel, Mark W., Hauser, Andreas, Chakraborty, Pradip, and Shatruk, Michael
- Subjects
- *
SPIN crossover , *ELECTRON configuration , *COOPERATIVE binding (Biochemistry) , *IRON compounds , *LIGHT absorption , *METASTABLE states , *CHELATES - Abstract
Homoleptic complexes [Fe(4bt)3](ClO4)2 (1), [Fe(2bt)3](ClO4)2 (2), and [Fe(3tpH)3](ClO4)2 (3) were obtained by a reaction between the Fe(II) precursor salt and the corresponding thiazole-based bidentate ligand (L = 4bt = 4,4′-bithiazole, 2bt = 2,2′-bithiazole, 3tpH = 3-(thiazol-2-yl)pyrazole). X-ray crystal structure determination revealed crystallization of solvent-free complex 1, a solvate 2·MeOH, and a co-crystal 3·2(3tpH). The crystal packing of all these complexes is dominated by one-dimensional interactions between the [Fe(L)3]2+ cations. These interactions are stronger in 2·MeOH and 3·2(3tpH), leading to cooperative and slightly hysteretic transitions between the high-spin and low-spin electronic configurations at ∼235 K and 159 K, respectively. In contrast, weaker intermolecular interactions in 1 result in a gradual spin crossover above 300 K, with the maximum fraction of the HS state ∼25% achieved at 400 K. Complexes 2 and 3·2(3tpH) exhibit light-induced excited spin state trapping (LIESST) under irradiation with white light or a 532 nm laser at 5 K. After the photoexcitation, the trapped metastable HS state relaxes to the ground LS state with the average relaxation temperature of 81 K and 68 K, respectively. Examination of the relaxation dynamics by optical absorption spectroscopy on a single crystal of 3·2(3tpH) revealed the sigmoidal shape of the relaxation curves at lower temperatures, attributed to cooperative effects, as well as a plateau at ∼10% of the HS fraction at intermediate temperatures, hinting at a more complex mechanism for the relaxation of the LIESST phase in this material. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Reduction of (pddi)Cr reveals redox noninnocence via C–C bond formation amidst competing electrophilicity: [(cpta)CrMen]− (n = 0, 1) and [(pta)Cr]−.
- Author
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D'Arpino, Alexander A., Wolczanski, Peter T., MacMillan, Samantha N., Cundari, Thomas R., and Krumov, Mihail R.
- Subjects
OXIDATION-reduction reaction ,CYCLOPROPANE ,CHELATES ,ANIONS - Abstract
Reversible cyclopropane formation is probed as a means of redox noninnocence in diimine/diamide chelates via reduction and complex anion formation. Competition from imine attack renders complications in the latter approach, and electrochemical measurements with calculational support provide the rationale. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Bi‐Functional Chelating Ligand Enables Ultra‐Stable Blue Emissive CsPbBr3 Nanoplatelets Film.
- Author
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Lin, Hao, Gao, Pei‐Li, Dong, Jia‐Yi, Li, Jie‐Lei, Lian, Zhen‐Dong, Xu, Jin‐Cheng, Ng, Kar Wei, Chen, Shi, Su, Shi‐Chen, Liu, Hong‐Chao, Wu, Zhao‐Xin, and Wang, Shuang‐Peng
- Subjects
- *
NANOPARTICLES , *CHELATES , *OPTICAL susceptibility , *THIN films , *LIGHT emitting diodes , *CHELATING agents , *PHOSPHORESCENCE - Abstract
Quantum‐confined perovskite CsPbBr3 Nanoplatelets (NPLs) have recently emerged as promising blue‐emitting materials for perovskite light‐emitting diodes (PeLEDs). Yet, their susceptibility to optical instability in solid films under ambient conditions poses a significant hindrance. This study introduces a novel chelating strategy that utilizes metal manganese ions and multidentate ligands, markedly improving the structural stability, and emission efficiency of NPLs. The approach involves adding Diethylenetriaminepentaacetic acid (DTPA) to the perovskite precursor solution, which allows for strong coordination to surface [PbBr6]4− octahedrons via its multiple chelation sites. Ensuing metal manganese ion integration during the purification phase addresses Pb2+ and Br− site vacancies, culminating in near‐perfect octahedral structures with significantly fewer vacancies. These metal manganese ions are then further immobilized on the NPLs surface by the chelating effect of unbound DTPA functional groups. The resultant CsPbBr3 NPLs films demonstrate an impressive PLQY of 66%, showcasing remarkable air stability with consistent blue emission for up to 5 days. The CsPbBr3 NPLs‐based PeLEDs show electroluminescence at 460 nm with a current efficiency of 1.07 cd A−1 and a maximum luminance of 220 cd m−2. The proposed chelating strategy positions perovskite NPLs as an extremely promising prospect in future applications of high‐definition displays and high‐quality lighting. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. Developing New Organometal Complexes of Schiff Base Derivatives with Anticancer Potentials.
- Author
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Dinnimath, Basavaraj, Palled, Mahesh, Sutar, Shradha, Tashildar, Shradha, Chavan, Utkarsh, and Ganpule, Sampada
- Subjects
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SCHIFF base derivatives , *ORGANOMETALLIC compounds , *CHELATES , *SCHIFF bases , *HETEROCYCLIC compounds - Abstract
Organometallic compounds are gaining prominence today as they are found to be potent anticancer agents due to their diverse chemical nature along with the metal with which they are chelated. In these organometallic compounds, many different hetero-organic compounds like Schiff bases, Indoles, Quinolines, Pyrroles are chelated with different metals. As these heterocyclic compounds are proven cytotoxic agents at a higher dose, their potency get enhanced by many fold by metal complexation. Schiff base derivatives are reportedly more powerful agents against tumours of different types, they are gaining prominence as antitumour agents. In this present study, different derivatives of Schiff bases are synthesized and chelated with Aluminium (Al) and characterised with IR, NMR, LCMS and also subjected to metal analysis by ICPMS. Later, these compounds were screened by in vitro analysis of their cytotoxic potentials against cancer cell lines by MCF method and are found to be potent cytotoxic agents. Among all, MC-2 and MC-3 are nearer to the cytotoxic range given by NIH. Hence, we anticipate that although all the synthesized organometal complexes are potential cytotoxic agents, however MC 1 and MC 5 are significantly good cytotoxic agents. However, further study is needed to justify this claim. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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42. Combining Desferriferrioxamine B and 1‐Hydroxy‐2‐Piperidone ((PIPO)H) to Chelate Zirconium. Solution Structure of a Model Complex of the [89Zr]Zr−DFOcyclo*−mAb Radioimmunoconjugate.
- Author
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Mangin, Floriane, Fonquernie, Osian, Jewula, Pawel, Brandès, Stéphane, Penouilh, Marie‐José, Bonnin, Quentin, Vincent, Bruno, Espinosa, Enrique, Aubert, Emmanuel, Meyer, Michel, and Chambron, Jean‐Claude
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ZIRCONIUM , *OVERHAUSER effect (Nuclear physics) , *CHELATES , *DENSITY functional theory , *NUCLEAR magnetic resonance spectroscopy - Abstract
89Zr−immunoPET is a hot topic as 89Zr cumulates the advantages of 64Cu and 124I without their drawbacks. We report the synthesis of a model ligand of a chiral bioconjugable tetrahydroxamic chelator combining the desferriferrioxamine B siderophore and 1‐hydroxy‐2‐piperidone ((PIPO)H), a chiral cyclic hydroxamic acid derivative, and the study by NMR spectroscopy of its zirconium complex. Nuclear Overhauser effect measurements (ROESY) indicated that the complex exists in the form of two diastereomers, in 77 : 23 ratio, resulting from the combination of the central chiralities at the 3‐C of the (PIPO)H component and at the Zr4+ cation. The 44 lowest energy structures out of more than 1000 configurations/conformations returned by calculations based on density functional theory were examined. Comparison of the ROESY data and the calculated interatomic H⋅⋅⋅H distances allowed us to select the most probable configuration and conformations of the major complex. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Egg yolk peptide‐iron chelate: preparation, conformational structure, chelating mechanism and stability in vitro.
- Author
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Wei, Shuaishuai, Huo, Jiaying, Lin, Jia, Zhang, Ziwei, Dong, Shijian, Ma, Lulu, and Li, Shugang
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EGG yolk , *CHELATES , *X-ray photoelectron spectroscopy , *IRON supplements , *PEPTIDES , *IRON ions - Abstract
Summary: In this study, a method to produce iron‐chelating peptides derived from egg yolk proteins was developed and optimised. The egg yolk proteins were enzymolysed and ultrafiltered to prepare egg yolk peptide (EYP), and then the EYP was chelated with Fe to produce egg yolk peptide‐Fe (EYP‐Fe). The optimised mass ratio of peptide to iron, pH, temperature and reaction time were found at 8:1, pH 8.0, 40 °C and 30 min, respectively. The mean particle size of EYP‐Fe was 389.2 ± 2.61 nm, and the chelating ratio was 95.38 ± 1.93%. The measurements of FTIR, X‐ray photoelectron spectroscopy (XPS) and NMR showed that ferrous ions mainly combined with the amino and carboxyl of EYP to form EYP‐Fe. In vitro stability studies have shown that the iron release rate of the EYP‐Fe is maintained at around 5% under alkaline conditions, and there is no significant difference in iron release rate under conditions of 30 °C–80 °C; besides, it has a lower iron release rate (18%) in gastrointestinal digestion compared to FeSO4 (97.93%), indicating that the EYP‐Fe has good heat tolerance, alkalinity and digestion tolerance. The above results provide a scientific basis for the use of EYP‐Fe derived from egg yolk protein as a potential alternative to iron supplements. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. A vicinal oxygen chelate protein facilitates viral infection by triggering the unfolded protein response in Nicotiana benthamiana.
- Author
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Guo, Zhihong, Jiang, Ning, Li, Menglin, Guo, Hongfang, Liu, Qi, Qin, Xinyu, Zhang, Zongying, Han, Chenggui, and Wang, Ying
- Subjects
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NICOTIANA benthamiana , *UNFOLDED protein response , *VIRUS diseases , *VIRAL proteins , *CHELATES , *LEUCINE zippers , *CUCUMBER mosaic virus , *MOSAIC viruses - Abstract
Vicinal oxygen chelate (VOC) proteins are members of an enzyme superfamily with dioxygenase or non‐dioxygenase activities. However, the biological functions of VOC proteins in plants are poorly understood. Here, we show that a VOC in Nicotiana benthamiana (NbVOC1) facilitates viral infection. NbVOC1 was significantly induced by infection by beet necrotic yellow vein virus (BNYVV). Transient overexpression of NbVOC1 or its homolog from Beta vulgaris (BvVOC1) enhanced BNYVV infection in N. benthamiana, which required the nuclear localization of VOC1. Consistent with this result, overexpressing NbVOC1 facilitated BNYVV infection, whereas, knockdown and knockout of NbVOC1 inhibited BNYVV infection in transgenic N. benthamiana plants. NbVOC1 interacts with the basic leucine zipper transcription factors bZIP17/28, which enhances their self‐interaction and DNA binding to the promoters of unfolded protein response (UPR)‐related genes. We propose that bZIP17/28 directly binds to the NbVOC1 promoter and induces its transcription, forming a positive feedback loop to induce the UPR and facilitating BNYVV infection. Collectively, our results demonstrate that NbVOC1 positively regulates the UPR that enhances viral infection in plants. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. 2-(Pyridin-2-yl)quinazolin-4(3H)-one derivatives as new ligands for lanthanide(iii) cations.
- Author
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Krinochkin, A. P., Valieva, M. I., Kopchuk, D. S., Nosova, E. V., Kim, G. A., Sayfutdinova, Yu. M., Tanya, O. S., Zyryanov, G. V., and Charushin, V. N.
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RARE earth metals , *CARBOXYL group , *CATIONS , *QUINAZOLINE , *CUCURBITURIL , *LUMINESCENCE , *CHELATES - Abstract
A facile synthetic approach is reported toward ligands based on 2-(2-pyridyl)quinazoline, which are suitable for the preparation of both water-soluble and liposoluble chelate complexes with lanthanide(iii) cations. The ligands contain an additional rigid chelating moiety, such as the carboxyl group or the diethylenetriaminetetraacetic acid residue. The luminescence properties of the new cationic EuIII and TbIII complexes were studied. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Effect of Active Phase Precursor on Structural, Textural and Catalytic Properties of the Model NiO x /CeO 2 System Active in Dry Reforming of Methane.
- Author
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Legutko, Piotr, Kozieł, Marcin, Kowalczyk, Andrzej, Michalik, Marek, and Adamski, Andrzej
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CHEMICAL speciation ,GREENHOUSE gases ,NICKEL ,SYNTHESIS gas ,CHELATES - Abstract
The current paper is devoted to the synthesis of ceria-supported nickel-based catalysts starting from different precursors of the nickel active phase. Thermal decomposition of metal-containing precursors, deposited onto stable supports by dry impregnation, belongs to the industrially preferred, simple ways of catalyst preparation. The synthesized series of NiO
x /CeO2 catalysts have been tested in dry methane reforming (DMR), in which two greenhouse gases, i.e., CO2 and CH4 , are simultaneously converted into syngas. Both reaction progress and stability of the catalyst strongly depend on nickel speciation, which in turn can be determined by the nature of the chosen precursor. Contrary to relatively many studies focused on the importance of synthetic methods and conditions on nickel speciation, the effect of precursor nature on structural, textural, and functional properties of catalytic systems has neither been discussed much nor fully understood. The main goal of this paper was to elucidate the effect of precursors on the properties of NiOx /CeO2 . Consequences of the use of various nickel precursors (simple inorganic salts, organometallic complexes, and chelates) have been analyzed in detail from the viewpoint of their beneficial influence on the catalytic performance of NiOx /CeO2 system (containing 3 wt. % of Ni) tested in DMR. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
47. Structural Characteristics and Stability of Corn Peptide-iron Chelates.
- Author
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WU Hanshuo, REN Jie, ZHANG Xinxue, FU Shaowei, LI Shuguo, and LIU Wenying
- Subjects
STRUCTURAL stability ,CHELATES ,CORN ,ENERGY levels (Quantum mechanics) ,IRON supplements - Abstract
Corn peptide-iron chelates serve a dual purpose, enhancing the utilization of corn peptides while also offering a novel approach for the development of iron supplements. To examine the structural properties and thermal stability of corn peptide-iron chelates, samples of this compound were prepared from corn peptides and ferrous chloride. Following ultraviolet spectroscopy and thermogravimetric analysis, the binding sites of the identified corn peptide fragments and ferrous ions were simulated by molecular docking. The stability of the corn peptide-iron chelate was observed at different temperatures and pH values, as well as under different in vitro digestion conditions. The results showed that the ultraviolet absorption peak changed. More specifically, the characteristic absorption peak shifted from 274.99 nm to 275.01 nm. Moreover, the corn peptide and corn peptide-iron chelate were compared and found to differ in a number of their properties. Thermogravimetric analysis revealed residual rates of 34.94% and 18.74% for corn chelate and peptide, respectively, while thermal stability of the corn peptide-iron chelate was found to be significantly higher that of the corn peptide. The binding energy levels of FSAASYPDLIDALP and LQQRQQLLNPL with Fe
2+ were -50.50 and -48.61 kJ/mol, respectively, and the amino group of Asp8 (aspartic acid) was found to provide the ligand site. In addition, Pro7 (proline), Ser5 (serine), Tyr6 (tyrosine), and Leu7 (leucine) were found to bind to the ferrous ions to form hydrophobic interactions. The relative molecular masses were mostly below 1 000 u under the action of different temperatures. In addition, small peptides were more easily chelated and absorbed, and were stable under relatively alkaline conditions. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
48. Reactivities of phosphaalkynes towards diverse bis-silylenes.
- Author
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Sun, Xiaofei, Jin, Da, Maier, Stefanie, Hinz, Alexander, and Roesky, Peter W.
- Subjects
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SMALL molecules , *PHENYLENEDIAMINES , *MOLECULES , *CHELATES - Abstract
Bis-silylenes do not only act as strong chelating σ-donor ligands, but also exhibit cooperative behaviour in the activation of small molecules. Three different P–Si containing molecules were prepared from the reaction between tBuC≡P and different bis-silylenes, which are bridged by ferrocenediyl, diaminobenzene, or o-carborane. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Synthesis of Ru(II) and Os(II) photosensitizers bearing one 9,10-diamino-1,4,5,8-tetraazaphenanthrene scaffold.
- Author
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De Kreijger, Simon, Cauët, Emilie, Elias, Benjamin, and Troian-Gautier, Ludovic
- Subjects
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PHOTOSENSITIZERS , *ZINC porphyrins , *CHARGE exchange , *ACETONITRILE , *CHELATION , *CHELATES , *MOIETIES (Chemistry) - Abstract
The synthesis of eight Ru(II) and Os(II) photosensitizers bearing a common 9,10-disubstituted-1,4,5,8-tetraazaphenanthrene backbone is reported. With Os(II) photosensitizers, the 9,10-diNH2-1,4,5,8-tetraazaphenanthrene could be directly chelated onto the metal center via the heteroaromatic moiety, whereas similar conditions using Ru(II) resulted in the formation of an o-quinonediimine derivative. Hence, an alternative route, proceeding via the chelation of 9-NH2-10-NO2-1,4,5,8-tetraazaphenanthrene and subsequent ligand reduction of the corresponding photosensitizers was developed. Photosensitizers chelated via the polypyridyl-type moiety exhibited classical photophysical properties whereas the o-quinonediimine chelated Ru(II) analogues exhibited red-shifted absorption (520 nm) and no photoluminescence at room temperature in acetonitrile. The most promising photosensitizers were investigated for excited-state quenching with guanosine-5′-monophosphate in aqueous buffered conditions where reductive excited-state electron transfer was observed by nanosecond transient absorption spectroscopy. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. In Situ Growth and Dynamic Transformation of Nickel Chelate Nanoarrays into Reactive Surface Reconstituted Heterostructure for Overall Water Splitting.
- Author
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Huang, Qixiang, Wang, Fang, Sun, Zixu, Zhang, Biying, Li, WenZhen, Guo, Fangya, Liu, Yong, Ren, FengZhang, and Duan, Xiaoguang
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OXYGEN electrodes , *SURFACE reconstruction , *CHELATES , *METAL catalysts , *DENSITY functional theory , *PHOTOCATHODES - Abstract
In this work, self‐derivation and surface reconstruction strategies are innovatively introduced into the synthetic route of the metal complex‐derived catalysts. The in situ grown nanorod arrays of Ni‐based complex are prepared by a simple self‐derivation and rapid ligand chelation reaction. Furthermore, highly active heterogeneous electrocatalysts are developed by mild‐temperature calcination. Attributed to the maintained morphology and highly dispersed Ni/Ni(OH)2 heterojunction active sites, the as‐prepared electrode exhibits superior hydrogen evolution activity (38.4 mV–10 mA cm−2). In particular, the dynamic reconstruction during oxygen evolution through in situ Fourier transform infrared and in situ Raman spectroscopies are observed. The reconstructed Ni(OH)2/NiOOH by activation gives the electrode higher oxygen evolution performance (369 mV–200 mA cm−2). Further density functional theory mechanism studies disclose that Ni/Ni(OH)2 contributes to the adsorption of H* in hydrogen evolution and the activated Ni(OH)2/NiOOH optimizes the formation of intermediates in oxygen evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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