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961.
The first total synthesis of isoquinolinone alkaloid marinamide 1 and its methyl ester 2 was described. The key steps involved a regioselective Frieclel-Crafts reaction of 1-benzyl-1H-pyrrole to form the intermediate 8. 相似文献
962.
Eleven triazolyl substituted tetrahydrobenzofuran derivatives were synthesized in high yields as novel H+/K+‐ATPase inhibitor via one‐pot CuI‐catalyzed three‐component click reaction of azide, secondary amine and 3‐bromopropyne under mild conditions in water. Their structures were characterized by NMR, IR, ESI‐MS, elemental analysis and single‐crystal X‐ray diffraction analysis. Most of the target compounds exhibited better H+/K+‐ATPase inhibitory activity than commercial omeprazole with IC50 values less than 15 µmol·L?1. The initial structure‐activity analysis suggested that the triazole substituted by cycloalkyl, aromatic ring or O‐containing side‐chain seemed to be beneficial for enhancing the activity. 相似文献
963.
964.
Kyeong‐Ryoon Lee Sung Heum Choi Jin‐Sook Song Hyewon Seo Yoon‐Jee Chae Hwang Eui Cho Jin Hee Ahn Sung‐Hoon Ahn Myung Ae Bae 《Biomedical chromatography : BMC》2013,27(7):846-852
In this study, we developed a method for the determination of PF‐04620110 (2‐{(1r,4r)‐4‐[4‐(4‐amino‐5‐oxo‐7,8‐dihydropyrimido[5,4‐f][1,4]oxazepin‐6(5H)‐yl)phenyl]cyclohexyl}acetic acid), a novel diacylglycerol acyltransferase 1 (DGAT‐1) inhibitor, in rat plasma and validated it using liquid chromatography–tandem mass spectrometry (LC‐MS/MS). Rat plasma samples were processed following a protein precipitation method by using acetonitrile and were then injected into an LC‐MS/MS system for quantification. PF‐04620110 and imipramine (internal standard) were separated using a Hypersil Gold C18 column, with a mixture of acetonitrile and 10 mm ammonium formate (90:10, v/v) as the mobile phase. The ion transitions monitored in positive‐ion mode [M + H]+ of multiple‐reaction monitoring were m/z 397.0 → 260.2 for PF‐04620110 and m/z 280.8 → 86.0 for imipramine. The detector response was specific and linear for PF‐04620110 at concentrations within the range 0.05–50 µg/mL and the signal‐to‐noise ratios for the samples were ≥10. The intra‐ and inter‐day precision and accuracy of the method matched the acceptance criteria for assay validation. PF‐04620110 was stable under various processing and/or handling conditions. PF‐04620110 concentrations in the rat plasma samples could be measured up to 24 h after intravenous or oral administration of PF‐04620110, suggesting that the assay is useful for pharmacokinetic studies in rats. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
965.
Graphdiyne(GDY)has characteristics of one-atom-thick two-dimensional layers comprising of sp and sp2 hybridized carbon atoms.The chemical and electronic structure gives GDY many unique and fascinating properties,such as rich chemical bonds,highly conjugated and super-large π structures,infinitely distributed pores and high inhomogeneity of charge distribution,etc. 相似文献
966.
Siyuan Li Feng Jin Mayavan Viji Hyeju Jo Jaeuk Sim Hak Sung Kim Heesoon Lee Jae-Kyung Jung 《Tetrahedron letters》2017,58(14):1417-1420
An efficient and facile two-step strategy for the synthesis of (Z)-aurone from arylacetylenes and salicyladehydes, via silver(I) nitrate mediated cyclization/oxidation in the presence of potassium carbonate has been developed. The key feature of our method was delicate cascade reaction, to provide the corresponding (Z)-aurone in high yield and good regio- and stereo selectivity. 相似文献
967.
Abstract Different methods for the determination of the local field anisotropy in liquid crystals are analysed and the problems resulting from their application are outlined. One such method, namely that based on the comparison of the polarization of resonance Raman scattering and absorption bands is studied in more detail. The method is applied to determine the structural anisotropy for the 4-n-pentyl-(4′-cyanophenyl) derivatives of benzene, cyclohexane and bicyclooctane. To account for the difference between the optical properties of the probe and of the solvent at the wavelength of the scattered light the local field factor is treated theoretically within the framework of an anisotropic continuous dielectric medium. 相似文献
968.
Haojing Song Jin Wang Rui Zhang Xiaoyan Liu Guiyan Yuan Chunmin Wei Wenjing Zhao Rong Li Benjie Wang Ruichen Guo 《Biomedical chromatography : BMC》2013,27(11):1398-1405
Bergenin is the major component of Ardisia creanta sims and Rodgersia sambucifolia hemsl with many biological activities. Although bergenin has been used to treat human diseases in China for man years, there is no report regarding its metabolism. This is the first report to separate and identify the metabolites of bergenin in vivo. In the study, HPLC/Q‐TOF‐MS/MS was used to investigate the metabolites of bergenin in vivo by analyzing the rat body fluid and feces samples. Three metabolites of bergenin were finally identified by the TIC chromatograms, and the structures were also confirmed by their MS2 spectra. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
969.
Four main chain polymeric metal complexes (P1–P4) based on 1,10‐phenanthroline metal complexes via the Heck coupling have been synthesized and characterized by Fourier transform infrared spectroscopy, 1H NMR, UV–Vis absorption, photoluminescence spectroscopy, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, elemental analysis, and cyclic voltammetry. To investigate their photovoltaic properties, the dye‐sensitized solar cells based on these polymers dyes are studied, under the illumination of AM 1.5G, 100 mW/cm2. The study results show the four polymers exhibit good thermally stable and the solar cells based on them have good device performance, and the maximum power conversion efficiency is up to 0.735% for the solar cells based on P3 with a short‐circuit current (Jsc) of 1.68 mA/cm2 and an open‐circuit voltage (Voc) of 0.62 V. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
970.
The EPR spectra of manganese(II) ions on sulfonated polystyrene cross-linked with either pure meta or pure para divinylbenzene show distinctions indicative of ionic environments of different symmetry. 相似文献