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31.
The resin-bound cyclic malonic acid ester 2 reacted with aryl isothiocyanate and alkyl halides to afford the key intermediate arylthioaminomethylene cyclic malonic ester resin 3.Subsequently,resin 3 proceeded thermal cyclizaiton giving the 2-alkylthio-4(1H)-quinolones in good yields and excellent purties. 相似文献
32.
本文采用脂质体/水分配系统来考察pH、磷脂的种类和荷电性对药物与有序磷脂膜结合的影响. 相似文献
33.
Simultaneous Determination of Cefepime and the Quinolones Garenoxacin, Moxifloxacin and Levofloxacin in Human Urine by HPLC-UV 总被引:1,自引:0,他引:1
J. A. Ocaña González M. Callejón Mochón F. J. Barragán de la Rosa 《Mikrochimica acta》2005,151(1-2):39-45
A liquid chromatographic method with a C18 column and acetonitrile/0.1 M phosphoric acid/ sodium hydroxide buffer (pH 3.0)/0.01 M n-octylamine (pH 3.0) as mobile phase in gradient mode has been developed and optimised for the simultaneous determination of the cephalosporin cefepime and the quinolones garenoxacin, levofloxacin and moxifloxacin. Identification and quantification was carried out with a diode-array UV detector, with working wavelengths of 256 nm for cefepime, 292 nm for levofloxacin, 294 nm for moxifloxacin and 282 nm for garenoxacin. The mobile flow-rate and sample volume injected were 1 mL min−1 and 20 µL, respectively. The retention times and detection limits for each antibiotic were 4.9 min and 1.9 µg mL−1 for cefepime, 7.5 min and 2.2 µg mL−1 for levofloxacin, 8.9 min and 2.7 µg mL−1 for moxifloxacin and 10.7 min and 1.8 µg mL−1 for garenoxacin, respectively. The method was applied to the determination of the four molecules in spiked samples of human urine. 相似文献
34.
In this work, the development of two solid-phase extraction procedures (off-line and on-line formats) for the identification and quantification of several (fluoro)quinolones in hospital sewage water by HPLC-UV is described. Both procedures are based on the use of C18 and anion exchange (SAX) sorbents for the preconcentration and clean-up steps, respectively, and all variables influencing both steps were optimised. In the off-line format, after its pH was adjusted to 2.5, sample was preconcentrated on a C18 cartridge and eluted with 4 mL of methanol/ammonia (94/6). The methanolic extract must be diluted up to 10 mL with water to allow quantitative retention of the analytes on the SAX cartridge. In the on-line format, the addition of 2.5% of NH4Cl to the sewage water sample (pH = 2.5) was necessary to increase the breakthrough volumes of the analytes in the C18 precolumn. Quantitative transfer of the (fluoro)quinolones from the C18 precolumn to the SAX precolumn was accomplished by pumping 2 mL of a mixture methanol/water (40/60, pH = 9.2) at 2 mL min(-1). Elution of the analytes from the SAX precolumn by means of the chromatographic mobile phase required the inclusion of an additional isocratic step at the beginning of the gradient program. Both off-line and on-line solid phase extraction procedures coupled to HPLC-UV were applied to the analysis of a sewage water sample collected in the sewer system at the output of the St Dimphna Hospital (Geel, Belgium). The fluoroquinolone ciprofloxacin was found in this sample and quantified at 5.8 +/- 0.4 microg L(-1) (off-line method) and 5.6 +/- 0.5 microg L(-1) (on-line method). The analysis of spiked samples containing the seven (fluoro)quinolones studied provided quantitative recoveries in all cases with low RSD values (from 6 to 12%), and all the analytes could be identified by means of their UV spectra with match factors varying from 950 to 985 depending on the (fluoro)quinolone. 相似文献
35.
Sian Fang Yuhao Jiang Qianqian Gan Qing Ruan Di Xiao Junbo Zhang 《Molecules (Basel, Switzerland)》2020,25(24)
In order to seek novel technetium-99m bacterial infection imaging agents, a ciprofloxacin xanthate (CPF2XT) was synthesized and radiolabeled with [99mTcN]2+ core to obtain the 99mTcN-CPF2XT complex, which exhibited high radiochemical purity, hydrophilicity, and good stability in vitro. The bacteria binding assay indicated that 99mTcN-CPF2XT had specificity to bacteria. A study of biodistribution in mice showed that 99mTcN-CPF2XT had a higher uptake in bacterial infection tissues than in turpentine-induced abscesses, indicating that it could distinguish bacterial infection from sterile inflammation. Compared to 99mTcN-CPFXDTC, the abscess/blood and abscess/muscle ratios of 99mTcN-CPF2XT were higher and the uptakes of 99mTcN-CPF2XT in the liver and lung were obviously decreased. The results suggested that 99mTcN-CPF2XT would be a potential bacterial infection imaging agent. 相似文献
36.
This paper presents the multiresidue determination of the series of quinolones regulated by the European Union (marbofloxacin, ciprofloxacin, danofloxacin, enrofloxacin, sarafloxacin, difloxacin, oxolinic acid and flumequine) in bovine and porcine plasma using capillary electrophoresis and liquid chromatography with ultraviolet detection (CE‐UV, LC‐UV), liquid chromatography–mass spectrometry and –tandem mass spectrometry (LC‐MS, LC‐MS/MS) methods. These procedures involve a sample preparation by solid‐phase extraction for clean‐up and preconcentration of the analytes before their injection into the separation system. All methods give satisfactory results in terms of linearity, precision, accuracy and limits of quantification. The suitability of the methods to determine quinolones was evaluated by determining the concentration of enrofloxacin and ciprofloxacin in real samples from pig plasma and cow plasma. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
37.
M.-G. A. Shvekhgeimer 《Chemistry of Heterocyclic Compounds》2001,37(4):385-443
Data published after 1979 on the chemical transformations of 2H-3,1-benzoxazine-2,4-diones (isatoic anhydrides), leading to the formation of other heterocyclic compounds, are reviewed, classified, and analyzed. 相似文献
38.
Caro E Marcé RM Cormack PA Sherrington DC Borrull F 《Journal of separation science》2006,29(9):1230-1236
A molecularly imprinted polymer (MIP) has been prepared for the first time with ciprofloxacin (CIPRO) as the template molecule, via a noncovalent synthetic procedure. Prior to its use as a sorbent in SPE, the MIP was evaluated chromatographically to confirm that it was indeed molecularly imprinted. The MIP was then used to extract CIPRO selectively from urine samples by means of a two-step SPE procedure in which a commercial Oasis cartridge and a molecularly imprinted SPE cartridge were combined in series. This approach allowed the matrix compounds present in the samples to be removed effectively. The urine extracts obtained after this two-step SPE procedure was applied were relatively clean compared to the original samples, and this made it possible to inject directly the extracts into a mass spectrometer and thus quantify CIPRO in urine samples at low levels and reduce the time of analysis. 相似文献
39.
A diversity-oriented method for the synthesis of novel poly-substituted pyrazolo[1,5-a]quinolines has been developed on the basis of an SNAr/Knoevenagel cyclization cascade reaction or an SNAr/Dieckmann–Thorpe cyclization cascade reaction. The methods provide a variety of poly-substituted pyrazolo[1,5-a]quinolines bearing an amino, alkyl or aryl substituent at the 5-position. In addition, a diversity-oriented method for the synthesis of 2-substituted pyrazolo[1,5-a]quinolines from a readily available 2-[[(trifluoromethyl)sulfonyl]oxy]pyrazolo[1,5-a]quinoline has also been disclosed. 相似文献
40.