104809-47-4Relevant articles and documents
Imaging and therapeutic applications of Zn(ii)-cryptolepine-curcumin molecular probes in cell apoptosis detection and photodynamic therapy
Huang, Xiao-Ling,Liang, Hong,Qin, Qi-Pin,Tan, Ming-Xiong,Wang, Zhen-Feng,Wei, Zu-Zhuang,Zou, Hua-Hong
, p. 3999 - 4002 (2020)
Novel red Zn(ii) complex-based fluorescent probes featuring cryptolepine-curcumin derivatives, namely, [Zn(BQ)Cl2] (BQ-Zn) and [Zn(BQ)(Cur)]Cl (BQCur-Zn), were developed for the simple and fluorescent label-free detection of apoptosis, an important biological process. The probes could synergistically promote mitochondrion-mediated apoptosis and enhance tumor therapeutic effects in vitro and vivo.
Kinetics of proton transfer between ortho substituted benzoic acids and the carbinol base of crystal violet in toluene. Ortho effect on the reactivity of benzoic acids in apolar aprotic solvents
Sen Gupta, Susanta K.,Mishra, Sangeeta
, p. 4616 - 4623 (2011)
Apolar aprotic solvents are particularly advantageous for investigating the intrinsic ortho effect free from complications of specific solvent effects. A kinetic study for toluene-phase proton transfers between ortho F, Cl, Br, I, OMe, OEt, OPh, OAc, Me, NO2, COMe, COPh, OH, NH2, and H benzoic acids and crystal violet carbinol base has shown the forward rate constant (log k+1) is the most appropriate reactivity parameter in toluene. log k+1 (toluene) as compared to other reported reactivity parameters in benzene, toluene, or chlorobenzene has been found more sensitive to the ortho substituent effect. The regression results of the correlation of log k+1 (toluene) of the acids (except OH and NH2 substituted ones) according to seven ortho effect models are all very significant, and the best result is given by Fujita-Nishiokas model. The overall analysis reveals that a substituents ortho effect pattern is a 58:24:18 ratio of its ordinary electrical, proximity electrical, and steric effects and that the proximity electrical effect is the major component to account for the peculiarity of the substituents ortho effect. The results further favor the transmission of this effect mainly through the molecular cavity. The effect may, however, be outweighed by the steric component for bulky enough substituents, e.g., Me. The enhanced strength exhibited by salicylic acid in toluene has been quantitatively described using Pytela-Lisas δHB i parameter. The abnormally high log k+1 observed for anthranilic acid in toluene has been ascribed to a very extensive homoconjugation in its acid-acid anion complex induced by the acids three hydrogen bond donors.
Immobilization of Au nanoparticles on poly(glycidyl methacrylate)-functionalized magnetic nanoparticles for enhanced catalytic application in the reduction of nitroarenes and Suzuki reaction
Pourjavadi, Ali,Kohestanian, Mohammad,Keshavarzi, Nahid
, (2020)
We report a novel strategy for the synthesis of magnetic nanocomposite for highly efficient catalysis. Poly(glycidyl methacrylate) (PGMA) chains were grafted to the surface of magnetic nanoparticles (MNPs) through surface-initiated reversible addition-fragmentation chain transfer polymerization. Then, the oxirane rings in the PGMA chains were opened with 2,6-diamino pyridine (DAP) molecules as ligands to prepare the solid support. Finally, this magnetic nanocomposite was used for the immobilization of gold nanoparticles. Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, transmission electron microscopy, scanning electron microscopy, gel permeation chromatography, vibrating sample magnetometry, and atomic absorption spectroscopy were used for characterization of the catalyst. The loading of gold nanoparticles on the solid support was 0.52 mmol/g. The catalytic activity of the prepared catalyst (MNP@PGMA@DAP@Au) was evaluated for the reduction of nitro compounds and C–C coupling reaction in water. The catalyst can be easily recovered and reused seven times without significant loss of catalytic activity.
The flavoenzyme azobenzene reductase AzoR from Escherichia coli binds roseoflavin mononucleotide (RoFMN) with high affinity and is less active in its RoFMN form
Langer, Simone,Nakanishi, Shinobu,Mathes, Tilo,Knaus, Tanja,Binter, Alexandra,Macheroux, Peter,Mase, Tomoko,Miyakawa, Takuya,Tanokura, Masaru,Mack, Matthias
, p. 4288 - 4295 (2013)
The Gram-positive bacterium Streptomyces davawensis is the only organism known to produce the antibiotic roseoflavin. Roseoflavin is a structural riboflavin analogue and is converted to the flavin mononucleotide (FMN) analogue roseoflavin mononucleotide (RoFMN) by flavokinase. FMN-dependent homodimeric azobenzene reductase (AzoR) (EC 1.7.1.6) from Escherichia coli was analyzed as a model enzyme. In vivo and in vitro experiments revealed that RoFMN binds to the AzoR apoenzyme with an even higher affinity compared to that of the "natural" cofactor FMN. Structural analysis (at a resolution of 1.07 A) revealed that RoFMN binding did not affect the overall topology of the enzyme and also did not interfere with dimerization of AzoR. The AzoR-RoFMN holoenzyme complex was found to be less active (30% of AzoR-FMN activity) in a standard assay. We provide evidence that the different physicochemical properties of RoFMN are responsible for its reduced cofactor activity.
Design, synthesis and biological evaluation of tacrine-1,2,3-triazole derivatives as potent cholinesterase inhibitors
Wu, Gaochan,Gao, Yun,Kang, Dongwei,Huang, Boshi,Huo, Zhipeng,Liu, Huiqing,Poongavanam, Vasanthanathan,Zhan, Peng,Liu, Xinyong
, p. 149 - 159 (2018)
We report herein the design and synthesis of a series of 11 novel tacrine-1,2,3-triazole derivatives via a Cu(i)-catalyzed alkyne-azide 1,3-dipolar cycloaddition (CuAAC) reaction. The newly synthesized compounds were evaluated for their inhibition activity against Electrophorus electricus acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BChE) as potential drug targets for Alzheimer's disease (AD). Among the designed compounds, compound 8a2 exhibited potent inhibition against AChE and BChE with IC50 values of 4.89 μM and 3.61 μM, respectively. Further structure-activity relationship (SAR) and molecular modeling studies may provide valuable insights into the design of better tacrine-triazole analogues with potential therapeutic applications for AD.
Indicator Dyes and Catalytic Nanoparticles for Irreversible Visual Hydrogen Sensing
Smith, Michael E.,Stastny, Angela L.,Lynch, John A.,Yu, Zhao,Zhang, Peng,Heineman, William R.
, p. 10651 - 10658 (2020)
Using ultraviolet-visible (UV-vis) absorption spectroscopy, we have tested the reactivity of various indicator molecules combined with catalytic bimetallic gold-palladium nanoparticles (Au-Pd NPs) in solution for an irreversible and visual response to H2. Our aim was to identify the most suitable indicator/Au-Pd NP system for the future development of a thin, wearable, and visual H2 sensor for noninvasive monitoring of in vivo Mg-implant biodegradation in research and clinical settings with fast response time. The indicators studied were bromothymol blue, methyl red, and resazurin, and the reactions of each system with H2 in the presence of Au-Pd NPs caused visual and irreversible color changes that were concluded to proceed via redox processes. The resazurin/Au-Pd NP system was deemed best-suited for our research objectives because (1) this system had the fastest color change response to H2 at levels relevant to in vivo Mg-implant biodegradation compared to the other indicator/Au-Pd NP systems tested, (2) the observed redox chemistry with H2 followed well-understood reaction pathways reported in the literature, and (3) the redox products were nontoxic and appropriate for medical applications. Studying the effects of the concentrations of H2, Au-Pd NPs, and resazurin on the color change response time within the resazurin/Au-Pd NP system revealed that the H2-sensing elements can be optimized to achieve a faster or slower color change with H2 by varying the relative amounts of resazurin and Au-Pd NPs in solution. The results from this study are significant for future optical H2 sensor design.
Electrochemical carboxylation of 2-iodoaromatic compounds
Korbi, B. Haouas,Adhoum,Boujlel
, p. 2557 - 2564 (2004)
The electrochemical reduction of a series of 2-iodoaromatic substituted compounds in acetonitrile under an atmospheric pressure of carbon dioxide leads to ortho-substitued aromatic carboxylic acid. The maximum yield of acid obtained by electrolysis performed in a diaphragm-less cell at low temperature (5°C) with a sacrificial magnesium anode and by the use of a low current density was slightly higher than 70%.
Discovery of Novel Tacrine-Pyrimidone Hybrids as Potent Dual AChE/GSK-3 Inhibitors for the Treatment of Alzheimer's Disease
Yao, Hong,Uras, Giuseppe,Zhang, Pengfei,Xu, Shengtao,Yin, Ying,Liu, Jie,Qin, Shuai,Li, Xinuo,Allen, Stephanie,Bai, Renren,Gong, Qi,Zhang, Haiyan,Zhu, Zheying,Xu, Jinyi
, p. 7483 - 7506 (2021)
Based on a multitarget strategy, a series of novel tacrine-pyrimidone hybrids were identified for the potential treatment of Alzheimer's disease (AD). Biological evaluation results demonstrated that these hybrids exhibited significant inhibitory activities toward acetylcholinesterase (AChE) and glycogen synthase kinase 3 (GSK-3). The optimal compound 27g possessed excellent dual AChE/GSK-3 inhibition both in terms of potency and equilibrium (AChE: IC50 = 51.1 nM; GSK-3β: IC50 = 89.3 nM) and displayed significant amelioration on cognitive deficits in scopolamine-induced amnesia mice and efficient reduction against phosphorylation of tau protein on Ser-199 and Ser-396 sites in glyceraldehyde (GA)-stimulated differentiated SH-SY5Y cells. Furthermore, compound 27g exhibited eligible pharmacokinetic properties, good kinase selectivity, and moderate neuroprotection against GA-induced reduction in cell viability and neurite damage in SH-SY5Y-derived neurons. The multifunctional profiles of compound 27g suggest that it deserves further investigation as a promising lead for the prospective treatment of AD.
A highly selective diarylethene fluorescence sensor of aluminum ion and its application
Fan, Congbin,Liu, Gang,Pu, Shouzhi,Wang, Huaxin,Zhao, Heng
, (2021)
A novel diarylethene derivative 1O with the unit of N-(2-(hydrazinecarbonyl)phenyl)benzamide was designed and synthesized successfully. The sensor showed excellent photochromism and specific fluorescent detection toward aluminum ion with rarely interfering. The emission intensity could increase nearly by 100 folds with aluminum ion and the color changed from dark to Aqua green. The low limit of detection (LOD) of 1O was determined as 3.26 × 10-8 mol L-1. Additionally, the sensor could be used in logic circuit and aluminum ion detection in untreated water.
Photocatalytic degradation of dyes in water: Case study of indigo and of indigo carmine
Vautier, Manon,Guillard, Chantal,Herrmann, Jean-Marie
, p. 46 - 59 (2001)
The TiO2/UV photocatalytic degradations of indigo and of indigo carmine have been investigated both in aqueous heterogeneous suspensions and in the solid state. In addition to prompt removal of the color, TiO2/UV-based photocatalysis
