CN
Search Within
527254
应用筛选条件
关键词:'527254'
显示 1-30 共 32 条结果 关于 "527254" 范围 论文
Konrad Kowalewski et al.
Journal of chromatography. A, 1218(41), 7264-7274 (2011-09-13)
A novel three-step analytical method was developed which enables the simultaneous detection and identification of multifunctional oxygenated products resulting from the reaction of α-pinene with ozone. The method consists of the following steps: conversion of carbonyl groups to methyloximes using
Anna Topolewska et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 990, 150-157 (2015-04-16)
Green leafy vegetables are valuable secondary sources of nutrients, including lipids, commonly consumed in developing countries. However, method development for the analysis of fatty acids is usually focused on the animal lipid samples, rarely including natural plant extracts. Hence, the
Kanchanavadee Amphaisri et al.
Journal of chromatography. A, 1218(7), 972-980 (2011-01-11)
On-site verification of the chemical weapon convention (CWC) requires provision for the detection and identification of alkyl phosphonic acids as well as some organic acids that are amenable to GC-MS only after derivatisation. Various derivatisation methods have been used for
Hélène Lebel et al.
The Journal of organic chemistry, 73(17), 6828-6830 (2008-07-30)
Rhodium- and copper-catalyzed methylenation reactions with trimethylsilyldiazomethane, triphenylphosphine, and 2-propanol were used to react chemoselectively with aldehydes, alkoxymethylketones, and trifluoromethylketones in substrates also containing a less reactive carbonyl group. Terminal alkenes were obtained in high yields, and no protecting group
Thomas W Moy et al.
Journal of chromatographic science, 41(7), 343-349 (2003-08-12)
A multiresidue pesticide methodology is studied and results for acidics are reported here, with base/neutral to follow. This work studies a literature procedure as a possible general approach to many pesticides and potentially other analytes that are considered to be
Y Park et al.
Journal of agricultural and food chemistry, 49(3), 1158-1164 (2001-04-21)
Four different methods for methylating conjugated linoleic acid (CLA) were compared. The HCl/MeOH and BF(3)/MeOH methods were tested under different time and temperature combinations. Increasing temperature and/or incubation time for either method decreased the cis-9,trans-11 and trans-10,cis-12 isomers, but trans-9,trans-11/trans-10,trans-12
Lucas Actis-Goretta et al.
Journal of chromatography. A, 1245, 150-157 (2012-06-06)
(-)-Epicatechin, an abundant dietary polyphenol found mainly in cocoa and tea, is known to extensively undergo metabolism after ingestion giving rise to a complex series of conjugated metabolites including numerous isomers. In the present study, the combination of fractionation, chemical
Jin Woo Park et al.
Archives of pharmacal research, 37(12), 1560-1569 (2013-11-21)
Risedronate is widely used clinically to treat osteoporosis, Paget's disease, hypercalcemia, bone metastasis, and multiple myeloma. However, its oral efficacy is restricted due to its low bioavailability and severe gastrointestinal adverse effects. This study was designed to evaluate the effect
Taki Nishimura et al.
Molecular cell, 75(5), 1043-1057 (2019-08-14)
The plasma membrane (PM) is composed of a complex lipid mixture that forms heterogeneous membrane environments. Yet, how small-scale lipid organization controls physiological events at the PM remains largely unknown. Here, we show that ORP-related Osh lipid exchange proteins are
Andreas Ranz et al.
Journal of separation science, 31(4), 746-752 (2008-02-12)
In the present study, the preparation of methyl esters of chlorophenoxy acids with trimethylsilyldiazomethane (TMSD) is reported. TMSD is a mild and safe alternative to the highly toxic, thermally labile, and explosive diazomethane. Due to the novelty of this method
Liquid chromatography-mass spectrometry analysis of five bisphosphonates in equine urine and plasma.
April S Y Wong et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 998-999, 1-7 (2015-07-06)
Bisphosphonates are used in the management of skeletal disorder in humans and horses, with tiludronic acid being the first licensed veterinary medicine in the treatment of lameness associated with degenerative joint disease. Bisphosphonates are prohibited in horseracing according to Article
Homologation reaction of ketones with diazo compounds.
Candeias N R
Chemical Reviews, 116(5), 2937-2981 (2016)
T J van 't Erve et al.
Environment international, 36(8), 835-842 (2010-04-14)
Diazomethane is a highly explosive and toxic gas routinely employed for the quantitative and clean derivatization of phenols. We investigated the commercially available trimethylsilyldiazomethane in the presence of diisopropylethylamine as a safe, non-explosive and less-toxic alternative using six phenolic polychlorinated
Katrin Veldboer et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 879(22), 2073-2080 (2011-06-21)
A new method for the analysis of 1-hydroxy-2-imidazol-1-yl-phosphonoethyl phosphoric acid (zoledronic acid) in urine and blood samples has been developed. It consists of a derivatisation of the bisphosphonate with trimethylsilyl diazomethane under multiple methylester formation. The formed derivative can, in
Sussan Ghassabian et al.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences, 881-882, 34-41 (2011-12-27)
Risedronate is a commonly prescribed bisphosphonate for the treatment of bone disorders. Due to its high polarity and low oral bioavailability, low concentrations of risedronate are expected in human plasma and therefore a sensitive assay is required to serve in
Maria C Blassioli Moraes et al.
Phytochemistry, 69(1), 9-17 (2007-08-08)
Liquid phase extraction (LPE) and vapor phase extraction (VPE) methodologies were used to evaluate the impact of the plant activator, cis-jasmone, on the secondary metabolism of wheat, Triticum aestivum, var. Solstice. LPE allowed the measurement of benzoxazinoids, i.e. 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA)
Melissa Gulmezian et al.
Archives of biochemistry and biophysics, 467(2), 144-153 (2007-09-25)
The reversible redox chemistry of coenzyme Q serves a crucial function in respiratory electron transport. Biosynthesis of Q in Escherichia coli depends on the ubi genes. However, very little is known about UbiX, an enzyme thought to be involved in
S Takahashi et al.
Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan, 116(1), 39-49 (1996-01-01)
To quantify bile acids in biological samples, a solid phase extraction method was examined. This method is known as simpler procedures with less contamination compared with solvent extraction methods. Rat bile, feces and urine were used as biological samples. Since
Sean Flaherty et al.
Electrophoresis, 23(14), 2327-2332 (2002-09-05)
The investigation of emerging contaminant issues is a proactive effort in environmental analysis. As a part of this effort, sewage effluent is of current analytical interest because of the presence of pharmaceuticals and their metabolites and personal care products. The
A new, stable, and safe reagent for the homologation of ketones.
Hashimoto N
Tetrahedron Letters, 21(48), 4619-4622 (1980)
E Ostrowska et al.
Lipids, 35(10), 1147-1153 (2000-12-05)
Silver-ion high-performance liquid chromatography was used to fractionate a mixture of conjugated linoleic acid (CLA) isomers (as the free fatty acids, CLAFFA) in commercial CLA mixtures and biological samples. Due to the unchanged retention mechanism, it was assumed that the
Yoichi Noya et al.
Environmental science and pollution research international, 15(4), 318-321 (2008-04-26)
Diesel exhaust is believed to consist of thousands of organic constituents and is a major cause of urban pollution. We recently reported that a systematic separation procedure involving successive solvent extractions, followed by repeated column chromatography, resulted in the isolation
Jennifer A Dabrowski et al.
Organic letters, 12(16), 3598-3601 (2010-07-31)
Divergent reactivity is uncovered in the homologation of arylcyclobutanones with trimethylsilyldiazomethane. With Sc(OTf)(3) as catalyst, enolsilanes are obtained with a high preference for methylene migration. By contrast, Sc(hfac)(3) gives beta-ketosilanes with both regio- and diastereocontrol. Each adduct affords the cyclopentanone
Mechanism of methyl esterification of carboxylic acids by trimethylsilyldiazomethane.
Erik Kühnel et al.
Angewandte Chemie (International ed. in English), 46(37), 7075-7078 (2007-08-11)
Sean K J Devine et al.
Organic letters, 10(10), 1909-1911 (2008-04-12)
Palladium catalysts are shown to catalyze the three-component coupling of vinyl halides, trimethylsilyldiazomethane, and stabilized carbon nucleophiles. The reaction is believed to proceed through a palladium-carbene intermediate LX(R)PdCHSiMe 3 that undergoes migration of the vinyl substituent to the electrophilic carbene
Takeo Sakai et al.
Organic letters, 14(17), 4564-4567 (2012-08-21)
An equatorial attack of TMS-diazomethane was determined to be the first step of the BF(3)-promoted ring expansion reaction of six-membered ketones using TMS-diazomethane. The migration reaction occurred in a conformation in which the carbonyl oxygen and the TMS group were
Dragan Simovic et al.
The Journal of organic chemistry, 72(2), 650-653 (2007-01-16)
The 1,3-dipolar cycloaddition of trimethylsilyldiazomethane with alpha,beta-unsaturated esters was examined. The resulting 1-pyrazolines isomerize to regioisomeric 2-pyrazolines (a or b) or undergo desilylation (c). Acrylates yield only b or c. beta-Substituted dipolarophiles may yield all three types of products. This
Natalia Migowska et al.
Analytical and bioanalytical chemistry, 397(7), 3029-3034 (2010-06-22)
Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most common groups of pharmaceuticals detected in environmental matrices. Although several derivatization procedures have been employed in the gas chromatographic analysis of NSAIDs, the application of trimethylsilyldiazomethane has never yet been reported. This
Antonella Leggio et al.
Chemical biology & drug design, 73(3), 287-291 (2009-02-12)
A study of the methylation of N-nosyl-alpha-amino acids and derivatives with trimethylsilyldiazomethane is here reported. Trimethylsilyldiazomethane allows the chemo-specific methylation of the carboxyl function of N-nosyl-alpha-amino acids in high yields and purity. This method provides a practical route to N-methyl-alpha-amino
Meixia Chen et al.
Analytical and bioanalytical chemistry, 402(2), 791-798 (2011-10-18)
Alendronate is an important representative of bisphosphonates, strongly polar compounds that lack chromophores. With rare exceptions, derivatization of the analytes is necessary for bioanalysis. In this study, a rapid liquid chromatography-tandem mass spectrometry method employing pre-column derivatization was developed and
1/2