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排序方式: 共有406条查询结果,搜索用时 46 毫秒
91.
92.
B. Nunnally S. S. Park K. Patel M. Hong X. Zhang S. -X. Wang B. Rener A. Reed-Bogan O. Salas-Solano W. Lau M. Girard H. Carnegie V. Garcia-Cañas K. C. Cheng M. Zeng M. Ruesch R. Frazier C. Jochheim K. Natarajan K. Jessop M. Saeed F. Moffatt S. Madren S. Thiam K. Altria 《Chromatographia》2006,64(5-6):359-368
An international project team (including members from US, Canada and UK) has been formed from a number of interested biopharmaceutical companies and regulatory authorities to conduct a cross-organisation collaboration exercise. The results from this exercise demonstrate the robustness of CE-SDS across eight different organisations that used instruments of the same equipment model, the same reagents, and the same methodology. Data generated from the analysis of a series of molecular weight markers showed very good precision with regards to relative migration time (RMT) both within and between organisations. The apparent molecular weight of bovine serum albumin (BSA) was measured with good precision to within approximately 2% RSD across the participants. A representative IgG sample showed similar results with regards to relative migration time of its 3 main components, IgG Light Chain, IgG Non-glycosylated Heavy Chain, and IgG Heavy Chain. Fractional peak area for each peak also showed good agreement, with less than 9% RSD for all peaks. This exercise will facilitate both increased regulatory and industrial opinion of CE for biopharmaceutical analysis.CE in the Biotechnology & Pharmaceutical Industries: 7th Symposium on the Practical Applications for the Analysis of Proteins, Nucleotides and Small Molecules, Montreal, Canada, August 12–16, 2005 相似文献
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Ostwald Cohen Kohlrausch Heydweiller van't Hoff A. Naumann A. Rücker Arrhenius Walker Shields J. Walker E. Aston C. Kullgren Bredig Fraenkel W. E. Pawloff D. G. Gerassimoff Seth E. Moody R. W. Wood Will Koelichen M. Le Blanc K. Novotny Gernez H. Goldschmidt O. Girard Hantzsch Sebald G. Wiedemann B. E. Moore Dibbits W. Müller A. Birnbaum 《Analytical and bioanalytical chemistry》1907,46(2-3):159-165
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Felpin FX Girard S Vo-Thanh G Robins RJ Villiéras J Lebreton J 《The Journal of organic chemistry》2001,66(19):6305-6312
An enantiomeric synthesis of six piperidine and pyrrolidine alkaloids, (S)-nornicotine 1, (S)-nicotine 2, (S)-anatabine 3, (S)-N-methylanatabine 4, (S)-anabasine 5, and (S)-N-methylanabasine 6, known as natural products in tobacco, was established from a common chiral homoallylic (S)-3-(1-azido-but-3-enyl)-pyridine 15. An intramolecular hydroboration-cycloalkylation of the homoallylic azide intermediate 15 served as the key step in the pyrrolidine ring formation. A ring closing metathesis reaction (RCM) of a diethylenic amine intermediate (S)-allyl-(1-pyridin-3-yl-but-3-enyl)-carbamic acid benzyl ester 20 served as the key step in the piperidine ring formation. From the commercially available 3-pyridinecarboxaldehyde 13, a short and convenient enantiomeric synthesis of tobacco alkaloids is described: (S)-nornicotine 1 (5 steps, with an overall yield of 70%), (S)-nicotine 2 (6 steps, 65%), (S)-anatabine 3 (8 steps, 30%), (S)-N-methylanatabine 4 (8 steps, 25%), (S)-anabasine 5 (8 steps, 35%), and (S)-N-methylanabasine 6 (8 steps, 25%). 相似文献
98.
Nicolas Girard 《Tetrahedron letters》2007,48(23):4097-4099
A stereospecific synthesis of dendrobates (±)-alkaloid 241D is described. Key steps in this approach involved the stepwise electrochemical synthesis of C-4 substituted α-aminonitriles and their alkylation with iodomethane and 1-bromononane, respectively. The N-aryl group was removed in the last step through a Birch dearomatization followed by the hydrolysis of the intermediate dienamines. 相似文献
99.
The kinetics of precipitation reactions with110AgNO3 of some di (β-chlorethyl) amine derivates and hydrochlorides with esters of N-(p-aminobenzoyl)-L-aspartic acid as carriers in dimethylformamide-water mixture, were studied. The rate constants of these reactions were of the order of 10?4 1 · mol?1 · min?1. The concentrations of the corresponding hydrochloride solutions were measured by radiometric titration with110AgNO3 solution of given concentration. 相似文献
100.