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101.
102.
Sequential Cu-catalyzed amidation-base-mediated camps cyclization: a two-step synthesis of 2-Aryl-4-quinolones from o-halophenones 总被引:1,自引:0,他引:1
A direct two-step method for the preparation of 2-aryl- and 2-vinyl-4-quinolones that utilizes a copper-catalyzed amidation of o-halophenones followed by a base-promoted Camps cyclization of the resulting N-(2-ketoaryl)amides is described. With CuI, a diamine ligand, and base as the catalyst system, the amidation reactions proceed in good yields for a range of aryl, heteroaryl, and vinyl amides. The subsequent Camps cyclization efficiently provides the desired 4-quinolones with the conditions that are described. 相似文献
103.
Pierce CY Barr JR Woolfitt AR Moura H Shaw EI Thompson HA Massung RF Fernandez FM 《Analytica chimica acta》2007,583(1):23-31
Accurate bacterial identification is important in diagnosing disease and in microbial forensics. Coxiella burnetii, a highly infective microorganism causative of the human disease Q fever, is now considered a U.S. category B potential bioterrorism agent. We report here an approach for the confirmatory identification of C. burnetii at the strain level which involves the combined use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and supervised pattern recognition via Partial Least Squares-Discriminant Analysis (PLS-DA). C. burnetii isolates investigated in this study included the following prototype strains from different geographical and/or historical origins and with different antigenic properties: Nine Mile I, Australian QD, M44, KAV, PAV, Henzerling, and Ohio. After culture and purification following standard protocols, linear MALDI-TOF mass spectra of pure bacterial cultures were acquired in positive ion mode. Mass spectral data were normalized, baseline-corrected, denoised, binarized and modeled by PLS-DA under crossvalidation conditions. Robustness with respect to uncontrolled variations in the sample preparation and MALDI analysis protocol was assessed by repeating the experiment on five different days spanning a period of 6 months. The method was validated by the prediction of unknown C. burnetii samples in an independent test set with 100% sensitivity and specificity for five out of six strain classes. 相似文献
104.
Pierce CY Barr JR Cody RB Massung RF Woolfitt AR Moura H Thompson HA Fernandez FM 《Chemical communications (Cambridge, England)》2007,(8):807-809
Direct analysis in real time (DART) is implemented on a time-of-flight (TOF) mass spectrometer, and used for the generation of fatty acid methyl esters (FAMEs) ions from whole bacterial cells. 相似文献
105.
106.
James J. Harrison Anatoli Onopchenko Michael T. Cheng Carrie Y. Chan 《Journal of polymer science. Part A, Polymer chemistry》2000,38(1):152-160
The Na2CO3‐promoted polymerization of 1,3‐dioxolan‐2‐one (I) to afford poly(ethylene glycol) III was reinvestigated. The reaction appeared to involve a nucleophilic attack against the carbonyl and methylene groups of I to afford poly(carbonate) II with poly(ethylene glycol) linkages and ethylene oxide IV as a side product (10–22%). As the reaction progressed, poly(carbonate) II decreased and poly(ethylene glycol) III increased. Under some conditions, poly(ethylene glycol)s V and VI with vinyl ether terminal groups were formed unexpectedly. The formation of unsaturated products during the polymerization of I/EO (ethylene oxide) has not been reported in the literature. We believe that vinyl ethers were formed from the degradation of poly(carbonate)s and were accompanied by a reduction in molecular weight. The structures of vinyl ethers V and VI were confirmed by hydrogenation of the double bond into the ethyl ether group in VII and VIII, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 152–160, 2000 相似文献
107.
Aiden M. Lane Ny T. C. Luong Jordan C. Kelly Martin J. Neal Jeremiah Jamrom Aaron J. Bloomfield Paul A. Lummis Thomas D. Montgomery Daniel T. Chase 《Molecules (Basel, Switzerland)》2022,27(23)
A series of boron, aluminum, gallium, and indium chelates containing the underexplored bis(phenolate) aza-dipyrromethene (aza-DIPY) core were prepared. These compounds were found to possess near-infrared absorption and emission profiles in the 710 to 770 nm domain and exhibit quantum yield values up to 14%. X-ray diffraction analysis revealed that heavier group 13 bis(phenolate) aza-DIPY chelates possessed octahedral geometries with either THF or pyridine groups occupying the axial positions as opposed to the tetrahedral geometry of the boron chelate. 相似文献
108.
Transmission Raman spectroscopy is employed for the first time to analyse model formulations comprising tabletted cocrystals. The ability of transmission Raman to differentiate between formulations on the basis of both drug loading and drug chemistry (cocrystal versus separate components) is investigated. 相似文献
109.
Brandon J. O'Neill David H. K. Jackson Anthony J. Crisci Carrie A. Farberow Fengyuan Shi Ana C. Alba‐Rubio Junling Lu Paul J. Dietrich Xiangkui Gu Christopher L. Marshall Peter C. Stair Jeffrey W. Elam Jeffrey T. Miller Fabio H. Ribeiro Paul M. Voyles Jeffrey Greeley Manos Mavrikakis Susannah L. Scott Thomas F. Kuech James A. Dumesic 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2013,125(51):14068-14068
110.
Dudzinski KM Brown SJ Lammers M Lucke K Mann DA Simard P Wall CC Rasmussen MH Magnúsdóttir EE Tougaard J Eriksen N 《The Journal of the Acoustical Society of America》2011,129(1):436-448
Deployment of any type of measuring device into the ocean, whether to shallow or deeper depths, is accompanied by the hope that this equipment and associated data will be recovered. The ocean is harsh on gear. Salt water corrodes. Currents, tides, surge, storms, and winds collaborate to increase the severity of the conditions that monitoring devices will endure. All ocean-related research has encountered the situations described in this paper. In collating the details of various deployment and recovery scenarios related to stationary passive acoustic monitoring use in the ocean, it is the intent of this paper to share trouble-shooting successes and failures to guide future work with this gear to monitor marine mammal, fish, and ambient (biologic and anthropogenic) sounds in the ocean-in both coastal and open waters. 相似文献