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941.
Yixuan Tang Shihui Huang Xingxing Chen Junzhang Huang Qianwen Lin Lei Huang Shuping Wang Qihua Zhu Yungen Xu Yi Zou 《Molecules (Basel, Switzerland)》2022,27(19)
Protein arginine methyltransferases 5 (PRMT5) is a clinically promising epigenetic target that is upregulated in a variety of tumors. Currently, there are several PRMT5 inhibitors under preclinical or clinical development, however the established clinical inhibitors show favorable toxicity. Thus, it remains an unmet need to discover novel and structurally diverse PRMT5 inhibitors with characterized therapeutic utility. Herein, a series of tetrahydroisoquinoline (THIQ) derivatives were designed and synthesized as PRMT5 inhibitors using GSK-3326595 as the lead compound. Among them, compound 20 (IC50: 4.2 nM) exhibits more potent PRMT5 inhibitory activity than GSK-3326595 (IC50: 9.2 nM). In addition, compound 20 shows high anti-proliferative effects on MV-4-11 and MDA-MB-468 tumor cells and low cytotoxicity on AML-12 hepatocytes. Furthermore, compound 20 possesses acceptable pharmacokinetic profiles and displays considerable in vivo antitumor efficacy in a MV-4-11 xenograft model. Taken together, compound 20 is an antitumor compound worthy of further study. 相似文献
942.
Yeye Du Zhihong Chen Haiyang Wei Shuangjie Zhu Kezhou Cai 《Molecules (Basel, Switzerland)》2022,27(21)
The aim of this study was to isolate and identify antioxidative peptide from goose liver hydrolysate (GLHP) for ameliorating oxidative stress damage by alcohol in HHL-5 hepatocytes. In this research, the target antioxidative peptides in GLHP were separated, purified, and identified via a tangential flow ultrafiltration system combined with size exclusion chromatography (SEC), ion exchange chromatography (IEC), reversed-phase liquid chromatography (RP-LC), and LC-MS/MS. The results suggested that the amino acid sequence of the target antioxidative peptide for ameliorating alcohol-mediated oxidative stress damage in HHL-5 hepatocytes was Leu-Pro-Leu-Pro-Phe-Pro (LPLPFP), which had a molecular weight of 683.41 Da, and was derived from NADH-ubiquinone oxidoreductase chain 1 in goose liver. In addition, LPLPFP was confirmed to have a satisfactory stability and maintained high hepatic protective activity in a simulated gastrointestinal digestion. Moreover, the mechanism of LPLPFP prevented against oxidative stress damage in HHL-5 hepatocytes was attributed to inhibiting the production of reactive oxide species (ROS) by upregulating genes expression in the Ahr-NQO1 signal pathway. In conclusion, these results indicated that dietary GLHP supplementation could ameliorate alcohol-mediated oxidative stress damage and provide an affordable dietary intervention strategy to prevent alcohol-mediated hepatocyte damage. 相似文献
943.
2-[(3-Aminophenyl)sulfonyl] ethanol hydrogen sulfate (APSES) is an important intermediate for reactive dyes.It can be used to synthesize KN type reactive dyes, which have broad colour spectra,good water solubility, excellent adaptability for different dye technique,etc. Synthesis of APSES were currently developed by Kato Kuniok et al[1] and Sanki[2].Kato had attempted to synthesize of APSES by reaction of sodium benzenesulfinate as raw material with ethylene oxide to obtain 2-phenylsulfonyl ethanol(PSE). The PSE could further be nitrated and hydrogenated to obtain 2-[(3-aminophenyl)sulfonyl]ethanol (APSE). Finally,APSE was reacted with oleum to obtain 2-[(3-aminophenyl) sulfonyl] ethanol hydrogen sulfate (APSES). Sanki had discoved a new synthetic method for the PSE. The PSE was prepared by first reaction of thiophenol as raw material with chloroethanol, and then by oxidation with hydrogen peroxide.The above mentioned two methods are not easily be adopted in industries at home. The shortage and cost of the thiophenol and sodium benzenesulfinate are mainly limited. We modificated a new synthetic pathway for APSES by five steps. The experimental procedures are shown the following. 相似文献
944.
Jinyu Sun Yaming Zhou Guangshan Zhu Rongjing Yang Dongyuan Zhao 《Journal of solid state chemistry》2006,179(4):1230-1236
A basic zinc nitrate, [Zn(OH)(NO3)]n with a novel framework reported herein is prepared by solvothermal synthesis, and holds a rare three-dimensional (10,3)-d net called by Wells. It crystallizes in orthorhombic, space group, Pna21 (No. 33), , , , Z=4, , , , 3.49<θ<27.51, , R1=0.029, wR2=0.0773 for 697 (I>2σ(I)) of 1728 [R(int)=0.0246] unique reflections and 59 parameters. GOF=1.073. Interestingly this basic zinc nitrate, [Zn(OH)(NO3)]n behaves well at removal capacity for hydrogen chloride gas, 20.3 g HCl/100 g, and its framework is not destroyed yet. This adsorption character may be useful for the removal of toxic gases in the environment. 相似文献
945.
A wide size range of SiO2 particles were synthesized and were used as enzyme immobilization carriers to fabricate glucose biosensors. The size of the particles was in the range of 17-520 nm. These biosensors could be operated under physiological conditions (0.1 M phosphate buffer, pH 7.2). Particle size could affect the performance of SiO2 modified glucose biosensors drastically. The smaller particles had higher performance. The smallest SiO2 modified biosensor could work well in the glucose concentration range of 0.02-10 mM with a correlation coefficient of 0.9993. Its sensitivity was 2.08 μA/mM and the detection limit was 1.5 μM glucose. 相似文献
946.
H. Zhu R. Venkataraman N. Menaa W. Mueller S. Croft A. Berlizov 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):359-363
When radionuclides decay by cascading photons, the accuracy of the measured nuclide activity may be affected by true coincidence
summing effects. The effects can be quantified by Monte Carlo simulations that can handle correlated γ-and X-ray emissions
from a radionuclide. Analysis techniques are also available commercially to correct for the effects due to cascading γ-rays.
The MCNP-CP code was used to compute the effects in high purity germanium detectors for several commonly used nuclides and
geometries and the results were compared to measurements and an analysis technique. Excellent agreement in true coincidence
summing corrections predicted by MCNP-CP and the analysis technique was obtained. In addition, the X-ray true coincidence
summing effects were evaluated. 相似文献
947.
Unimolecular binary half-adders with orthogonal chemical inputs 总被引:1,自引:0,他引:1
Unimolecular half-adders based upon an arylvinyl-bipyridyl fluorophore platform were demonstrated where all the chemical input combinations were fully processed by half-adder molecules to generate the arithmetic results of the entire truth table. 相似文献
948.
Urinary excretion study of coenzyme Q10 in rats by ultra-performance liquid chromatography-mass spectrometry 总被引:1,自引:0,他引:1
A method based on ultra-performance liquid chromatography mass spectrometry (UPLC-MS) applying atmospheric pressure chemical ionization in the positive ion mode is developed for the determination of coenzyme Q10 (CoQ10) in rat urine. The assay involves the extraction of crude urine, fast liquid chromatography on a Waters Acquity UPLC BEH C18 column (1.7 microm, 1.0 x 50 mm), and selected ion monitoring detection using mass transition. The calibration range is found to be 0.05-25 microg/mL, with the lower limit of quantitation of 0.05 microg/mL. Intra- and inter-day precision (relative standard deviation) for CoQ10 in rat urine range from 0.7% to 15%, and accuracy expressed in recovery rates in urine is between 83% and 118%. The recovery of this method is found to be between 80% and 95% at three concentrations. The total cumulative recovery of CoQ10 is 1.16 +/- 1.05% (percentage of dose intake, n = 4) from rat urine collected over 30 h after oral administration of the drug. The UPLC-MS method described allows the quick determination of CoQ10 in rat urine with good precision and accuracy. It is suitable for further excretion studies of CoQ10 in animals. 相似文献
949.
Di CA Yu G Liu Y Xu X Wei D Song Y Sun Y Wang Y Zhu D Liu J Liu X Wu D 《Journal of the American Chemical Society》2006,128(51):16418-16419
The characteristics of organic field-effect transistors (OFETs) were dramatically improved by chemically modifying the surface of the bottom-contact Ag or Cu source-drain (D-S) electrodes with a simple solution method. The contact resistance and energetic mismatch typically observed with Ag D-S electrodes in pentacene bottom-contact OFETs can be properly eliminated when modified by the Ag-TCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane). The pentacene transistors with low-cost Ag-TCNQ-modified Ag bottom-contact electrodes exhibit outstanding electrical properties, which are comparable with that of the Au top-contact devices. It thus provides a novel way toward high-performance low-cost bottom-contact OFETs. 相似文献
950.
[reaction: see text] The coupling reaction of pinacolborane with aryl iodides under the catalysis of 10 mol % CuI and the action of sodium hydride in THF works at room temperature to provide corresponding arylboronates in good yields. Aryl bromides give poor conversion under these reaction conditions. 相似文献