2725-53-3Relevant academic research and scientific papers
A novel axially palladium(II)-Schiff base complex substituted silicon(IV) phthalocyanine: Synthesis, characterization, photophysicochemical properties and photodynamic antimicrobial chemotherapy activity against Staphylococcus aureus
Sen, Pinar,Nyokong, Tebello
, (2019)
In this study, a novel silicon(IV) phthalocyanine is reported for the first time as a phthalocyanine derivative bearing axially a palladium(II)-Schiff base complex. The photophysical and photochemical properties of the new Si(IV)Pc, such as absorption, fluorescence, singlet oxygen quantum yields, triplet state quantum yields and exited state lifetimes were measured in DMSO. The new silicon phthalocyanine displayed very low fluorescence, showing efficient intersystem crossing resulting in high triplet and high singlet oxygen quantum yields in DMSO. When compared with the unsubstituted SiPcCl2, the singlet oxygen quantum yield value (ΦΔ = 0.47) in relation to the triplet quantum yield (ΦT = 0.82), which is an important determinant for PDT applications, increased. The photodynamic antimicrobial chemotherapy activity (PACT) of new Si(IV)Pc towards Staphylococcus aureus was determined in comparison to the unsubstituted SiPcCl2. The results of the photodynamic antimicrobial effect study demonstrated that the Pd(II) complex substituted SiPc (5) possesses excellent photodynamic activity with a reduction percentage value of 99.94% and a log red value of 3.26.
Copper ion-selective fluorescent sensor based on the inner filter effect using a spiropyran derivative
Shao, Na,Zhang, Ying,Cheung, SinMan,Yang, RongHua,Chan, WingHong,Mo, Tain,Li, KeAn,Liu, Feng
, p. 7294 - 7303 (2005)
A highly selective copper(II) ion fluorescent sensor has been designed based on the UV-visible absorption of a spiropyran derivative coupled with the use of a metal porphyrin operative on the fluorescence inner filter effect. Spiropyrans, which combine the characteristics of metal binding and signal transduction, have been widely utilized in cationic ion recognition by UV-visible spectroscopy. In the present work, the viability of converting the absorption signal of the spiropyran molecule into a fluorescence signal was explored. On account of overlap of the absorption band of the spiropyran (λabs = 547 nm) in the presence of copper ion with the Q-band of an added fluorophore, zinc meso-tetraphenylporphyrin (λabs = 556 nm), the effective light absorbed by the porphyrin and concomitantly the emitted light intensity vary as a result of varying absorption of the spiropyran via fluorescence inner filter effect. The metal binding characteristic of the spiropyran presents an excellent selectivity for copper ion in comparison with several other heavy or transition metal ions. Since the changes in the absorbance of the absorber translate into exponential changes in fluorescence of the fluorophore, the novelty of the present device is that the analytical signal is more sensitive over that of the absorptiometry or that of the fluorometry using one single dye. To realize a practical fluorescent sensor, both the absorber and fluorophore were immobilized in a plasticized poly(vinyl chloride) membrane, and the sensing characteristics of the membrane for copper ion were investigated. The sensor is useful for measuring Cu2+ at concentrations ranging from 7.5 × 10-7 to 3.6 × 10 -5 M with a detection limit of 1.5 × 10-7 M. The sensor is chemically reversible, the fluorescence was switched off by immersing the membrane in copper ion solution and switched on by washing it with EDTA solution.
Zwitterionic macrocyclic metal sulfate extractants containing 3-dialkylaminomethylsalicylaldimine units
Plieger, Paul G.,Tasker, Peter A.,Galbraith, Stuart G.
, p. 313 - 318 (2004)
10,25-Di-tert-alkyl-14,21-dimethyl-3,6,14,21-tetraazatricyclo[21.3.1.18, 12]octacosa-1(27),2,6,8,10,12(28),23,25-octaene-27,28-diol macrocycles form Ni(II) and Cu(II) complexes in which the metal cation and the sulfate anion are bound in separated sites in a zwitterionic form of the ligand. The nonyl-substituted macrocycle shows a higher affinity for SO42- and a lower binding strength for Cu2+ than open chain analogues, the pH-dependences for which fall in ranges which allow loading of CuSO4 at pH ≈4 and easy stripping to recycle the ligand. X-Ray structure determinations of the Cu(II) and Ni(II) sulfate complexes of the tert-butyl substituted ligand suggest that the de-tuning of M2+-binding results from a distortion from planarity of the "salen" N2O22- donor set imposed by the incorporation of the hexamethylene strap in the ligand and reveal that the sulfate is bound as a hydrate in a 2:2:2:2, ligand-M2+-SO42--H2O, assembly.
Dual-functional probe based on rhodamine for sequential Cu2+ and ATP detection in vivo
Jin, Xilang,Gao, Jingkai,Xie, Pu,Yu, Mengchen,Wang, Ting,Zhou, Hongwei,Ma, Aijie,Wang, Qian,Leng, Xin,Zhang, Xianghan
, p. 657 - 664 (2018)
A rhodamine-based fluorescent probe for Cu2+ and ATP has been designed. The fluorescence intensity/absorbance was significantly enhanced upon the addition of Cu2+ owning to the opening of the spiro-ring of rhodamine, which quickly returned to the original level due to the reconstruction of the probe by the reacting with ATP. Cu2+/ATP-induced fluorescent intensity/aborbance changes showed a good linear relationship with the concentration of Cu2+/ATP in the range of 2–20 μM/0–10 μM with a detection limit of 0.1 μM/1.0 μM. The proposed method is simple in design and fast in operation, and is suitable for the reversible monitoring of Cu2+ and ATP in bioanalytical applications.
Structure-Based Design of Potent and Orally Active Isoindolinone Inhibitors of MDM2-p53 Protein-Protein Interaction
Chessari, Gianni,Hardcastle, Ian R.,Ahn, Jong Sook,Anil, Burcu,Anscombe, Elizabeth,Bawn, Ruth H.,Bevan, Luke D.,Blackburn, Timothy J.,Buck, Ildiko,Cano, Celine,Carbain, Benoit,Castro, Juan,Cons, Ben,Cully, Sarah J.,Endicott, Jane A.,Fazal, Lynsey,Golding, Bernard T.,Griffin, Roger J.,Haggerty, Karen,Harnor, Suzannah J.,Hearn, Keisha,Hobson, Stephen,Holvey, Rhian S.,Howard, Steven,Jennings, Claire E.,Johnson, Christopher N.,Lunec, John,Miller, Duncan C.,Newell, David R.,Noble, Martin E. M.,Reeks, Judith,Revill, Charlotte H.,Riedinger, Christiane,St. Denis, Jeffrey D.,Tamanini, Emiliano,Thomas, Huw,Thompson, Neil T.,Vinkovi?, Mladen,Wedge, Stephen R.,Williams, Pamela A.,Wilsher, Nicola E.,Zhang, Bian,Zhao, Yan
supporting information, p. 4071 - 4088 (2021/05/04)
Inhibition of murine double minute 2 (MDM2)-p53 protein-protein interaction with small molecules has been shown to reactivate p53 and inhibit tumor growth. Here, we describe rational, structure-guided, design of novel isoindolinone-based MDM2 inhibitors. MDM2 X-ray crystallography, quantum mechanics ligand-based design, and metabolite identification all contributed toward the discovery of potent in vitro and in vivo inhibitors of the MDM2-p53 interaction with representative compounds inducing cytostasis in an SJSA-1 osteosarcoma xenograft model following once-daily oral administration.
Enantioselective Hydroboration of Ketones Catalyzed by Rare-Earth-Metal Complexes Supported with Phenoxy-Functionalized TsDPEN Ligands
Yu, Qishun,Lu, Chengrong,Zhao, Bei
supporting information, p. 2529 - 2537 (2021/07/28)
Six novel chiral rare-earth-metal complexes bearing the phenoxy-functionalized TsDPEN ligand H3L1 (H3L1 = N-((1R,2R)-2-((3,5-di-Tert-butyl-2-hydroxybenzyl)amino)-1,2-diphenylethyl)-4-methylbenzenesulfonamide) were synthesized successfully and well characterized. The solid-state structures of four tetranuclear rare-earth-metal complexes [RE2L13]2 (RE = Nd (1), Sm (2), Eu (3), Gd (4)) and the dual-core yttrium complex Y2L13 (5) were determined by X-ray diffraction, respectively. The structure of lanthanum complex 6 was speculated by the 1H DOSY spectroscopy in THF-d8 together with DFT calculations. Complexes 1-5 were employed to catalyze the enantioselective hydroboration of ketones and α,β-unsaturated ketones using pinacolborane (HBpin) as a reductant, and complex 1 gave better outcomes in comparison to the others. The corresponding secondary alcohols were obtained in excellent yields and moderate ee values. The same results were also achieved using the combined catalyst system of the neodymium amide Nd[N(SiMe3)2]3 with the phenoxy-functionalized TsDPEN ligand H3L1 in a 1:1.5 molar ratio.
Unprecedented reductive cyclisation of salophen ligands to tetrahydroquinoxalines during metal complex formation
Dowsett, Mark R.,Lamb, Katie J.,North, Michael,Parker, Rachel R.,Whitwood, Adrian C.
supporting information, p. 4844 - 4847 (2020/05/13)
The synthesis of novel tetrahydroquinoxalines by a metal induced one-electron reductive cyclisation of salophen ligands was found to occur when a salophen ligand was treated with chromium(ii) chloride or decamethylcobaltocene.
Development of a Cofilin Inhibitor for the Treatment of Hemorrhagic Brain Injury-Induced Neuroinflammation
-
Paragraph 0035; 0074; 0075, (2020/12/08)
Compounds and methods for inhibiting cofilin activity or reducing total cofilin, improving motor deficits, attenuating LPS-induced microglial activation and inflammation, reducing microglial migration and proliferation, reducing TNF-α, reducing NF-κB, and improving motor deficits in a subject are described.
Phosphine-Catalyzed [3+2] Annulation of β-Sulfonamido-Substituted Enones with Sulfamate-Derived Cyclic Imines
Shi, Wangyu,Zhou, Leijie,Mao, Biming,Wang, Qijun,Wang, Chang,Zhang, Cheng,Li, Xuefeng,Xiao, Yumei,Guo, Hongchao
supporting information, p. 679 - 685 (2019/01/24)
Phosphine-catalyzed [3+2] annulation of β-sulfonamido-substituted enones and sulfamate-derived cyclic imines has been developed, giving a series of imidazoline derivatives in moderate to excellent yields with good to excellent diastereoselectivities. A scale-up reaction worked well under mild reaction conditions. A possible mechanism was proposed on the basis of the results obtained.
Synthesis of Monofunctionalized Calix[5]arenes
Ingenfeld, Bj?rn,Straub, Steffen,Fr?mbgen, Christopher,Lützen, Arne
, p. 676 - 684 (2017/11/16)
Seven OH-free and O -permethylated monofunctionalized calix[5]arenes carrying either additional methyl or tert -butyl groups are prepared following fragment condensation protocols. This strategy proves to be superior to previous approaches. Calix[5]arenes with free OH groups all adopt a cone conformation stabilized by a seam of hydrogen bonds at the lower rim. Post-condensation modifications, i.e., methylation of phenolic OH groups or functional group interconversions can also be achieved. Bulky tert -butyl groups are also found to stabilize the cone conformations of O -methylated compounds. These compounds offer versatile functional groups that make these concave molecules interesting building blocks for the synthesis of more sophisticated molecular architectures.
