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Natalia Shpiro 《合成通讯》2013,43(17):2265-2269
An improved synthesis of the potent MEK inhibitor PD184352 (2-(2-Chloro-4-iodo-phenylamino)-N-cyclopropylmethoxy-3,4-difluoro-benzamide)) is herein reported. This new and reproducible protocol provides a simple and efficient way of generating gram quantities of PD184352 with minimal purification. 相似文献
97.
Evgenyi V. Gryshkun Natalia V. Andrushko Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1027-1046
Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized. 相似文献
98.
Anatoli Tchigvintsev Dmitri Tchigvintsev Robert Flick Ana Popovic Aiping Dong Xiaohui Xu Greg Brown Wenyun Lu Hong Wu Hong Cui Ludmila Dombrowski Jeong Chan Joo Natalia Beloglazova Jinrong Min Alexei Savchenko Amy A. Caudy Joshua D. Rabinowitz Alexey G. Murzin Alexander F. Yakunin 《Chemistry & biology》2013,20(11):1386-1398
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Manuel Sergi Natalia Battista Camilla Montesano Roberta Curini Mauro Maccarrone Dario Compagnone 《Analytical and bioanalytical chemistry》2013,405(2-3):785-793
Endocannabinoids (ECs) are endogenous compounds that interact with type-1 and type-2 cannabinoid receptors (CB1 and CB2), as well as non-cannabinoid receptors. The multitude of roles attributed to ECs makes them an emerging target of pharmacotherapy for a number of disparate diseases. Here a high-throughput bioanalytical method based on micro SPE (μ-SPE) followed by LC-MS/MS analysis for the simultaneous determination of the two major endocannabinoids 2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine (anandamide, AEA) in human plasma is presented. The chromatographic conditions obtained with the fused-core column allowed a good separation in 10 min also of the AG isomers. A very simple and reliable extraction has been optimised by means of C18-modified tips: it requires only 100 μL of plasma and allows the use of minimal volumes of organic solvent. The present method allows a rapid and effective clean-up, which also minimises the isomerisation of 2-AG. The whole procedure has been validated following the FDA guidelines for bioanalytical methods validation: the satisfactory recovery values, the negligible matrix effect and the good values of accuracy and reproducibility make it a simple and high-throughput analytical tool for clinical and biochemical studies on endocannabinoid signaling in humans. Figure
Determination of the two major endocannabinoids in human plasma by μ-SPE followed by HPLC-MS/MS 相似文献
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Tyler T. Clikeman Dr. Igor V. Kuvychko Dr. Natalia B. Shustova Dr. Yu‐Sheng Chen Dr. Alexey A. Popov Dr. Olga V. Boltalina Prof. Steven H. Strauss 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(16):5070-5080
The sequential addition of CN? or CH3? and electrophiles to three perfluoroalkylfullerenes (PFAFs), Cs‐C70(CF3)8, C1‐C70(CF3)10, and Cs‐p‐C60(CF3)2, was carried out to determine the most reactive individual fullerene C atoms (as opposed to the most reactive C?C bonds, which has previously been studied). Each PFAF reacted with CH3? or CN? to generate metastable PFAF(CN)? or PFAF(CH3)22? species with high regioselectivity (i.e., one or two predominant isomers). They were treated with electrophiles E+ to generate PFAF(CN)(E) or PFAF(CH3)2(E)2 derivatives, also with high regioselectivity (E+=CN+, CH3+, or H+). All of the predominant products, characterized by mass spectrometry and 19F NMR spectroscopy, are new compounds. Some could be purified by HPLC to give single isomers. Two of them, C70(CF3)8(CN)2 and C70(CF3)10(CH3)2(CN)2, were characterized by single‐crystal X‐ray diffraction. DFT calculations were used to propose whether a particular reaction is under kinetic or thermodynamic control. 相似文献