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《化学分析计量》2014,(1)
<正>沃特世公司隆重发布新型WatersACQUITYQDaTM质谱检测器——能为色谱分离提供高质量质谱数据的质谱检测器。ACQUITY QDa质谱检测器经过专门设计,可作为色谱分离系统的完美补充,可以与沃特世超高效液相色谱ACQUITY UltraPerformance LC(UPLC),超高效合相色谱ACQUITY UltraPerformance Convergence ChromatographyTM(UPC2)、Alliance高效液相色谱(HPLC)、沃特世超临界流体色谱(SFC)和基于LC的纯化系统完美结合。解决了影响日常质谱应用的复杂性、仪器体积 相似文献
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《分析化学》2014,(3):435
2014年1月28日,沃特世公司推出了新型的Waters ACQUITY UPLC M-Class系统,这是业内首台涵盖纳升级至微升级的Ultra Performance LC(UPLC)超高效液相色谱系统,系统耐压高达15000 psi。将此系统与沃特世质谱仪联用,能够对复杂样品体系中含量极低的分子进行鉴定和定量,提供前所未有的高灵敏度。ACQUITY UPLC M-Class系统可用于蛋白质组学、代谢分析、代谢物鉴定和药代动力学研究等各个领域。同时,全新设计的可耐受15000 psi压力的亚2μm色谱柱,提供更快的分离速度、更高的峰容量和灵敏度。 相似文献
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陈秀 《分析测试技术与仪器》2016,(1):28-35
研究了27种胺类物质在与间甲基苯甲酰氯的衍生化过程中,活泼氢与衍生化试剂的反应情况.建立了超高液相色谱-质谱分析27种胺类衍生物的定性分析方法.使用Waters ACQUITY UPLCHSS T3色谱柱(Φ1.8μm,3.0 mm×150 mm)为分离柱,乙腈和甲酸(体积比为0.1%)水溶液为流动相,采用2种梯度洗脱程序,经液相色谱分离后,质谱采用电喷雾电离源正离子模式,以各种胺类衍生化合物的选择离子[M+H]+监测模式进行定性分析.试验发现,仪器检出限可达0.2 mg/L,可以用于胺类物质的快速定性检测. 相似文献
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建立了基于PRiME HLB通过型固相萃取净化-超高效液相色谱-高分辨质谱法(UPLC-HRMS)快速准确测定杨梅中29种常见农药残留的检测方法。杨梅样品经乙腈涡旋提取、盐析和PRiME HLB固相萃取净化后,以5 mmol/L乙酸铵水溶液和乙腈溶液作为流动相在Waters ACQUITY UPLC HSS T3色谱柱(100 mm×2.1 mm, 1.8 μm)上进行色谱分离,采用正离子电喷雾离子化模式(ESI+)和一级全扫描-数据依赖二级质谱扫描模式(Full mass-ddMS2),基质匹配外标法定量分析。该研究首先优化了液相色谱条件,重点考察了Waters ACQUITY UPLC HSS T3色谱柱和Waters ACQUITY UPLC BEH C18色谱柱对29种农药色谱行为的影响,结果表明Waters ACQUITY UPLC HSS T3色谱柱相比后者具有更强的色谱保留能力;流动相优化结果显示,相比于乙腈-甲酸水溶液体系和乙腈-甲酸-乙酸铵水溶液体系,乙腈-乙酸铵水溶液体系作为流动相时29种农药普遍具有更佳的色谱保留,部分农药的质谱响应有了显著的提高。此外,该研究通过考察3种不同净化方法的基质效应以优化杨梅中29种农药残留检测,实验结果表明,相比于GCB SPE和QuEChERS法两种净化方式,PRiME HLB法对于杨梅提取液具有较好的基质净化能力。在最佳实验条件下,29种农药在1.0~200.0 μg/L范围内呈现良好的线性关系(线性相关系数R2>0.999),方法检出限为2.0 μg/kg;低(6 μg/kg)、中(200 μg/kg)、高(400 μg/kg)3个加标水平下,29种农药的加标回收率为69.2%~135.6%,相对标准偏差为0.7%~14.6%。该方法具有快速、简便、灵敏和准确等优点,适用于理化实验室大批量样品的日常监测。 相似文献
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建立了在线二维液相色谱-四极杆飞行时间质谱检测头孢噻吩钠杂质谱的方法,有效地解决了流动相中含不挥发性磷酸盐的色谱系统不适合用于液相色谱-质谱快速鉴定杂质的难题。一维高效液相色谱(HPLC)以Symmetry C18为色谱柱,以磷酸盐缓冲液(pH 2.5)和乙腈梯度洗脱;二维以ACQUITY UPLC BEH C18为色谱柱,以0.1%(v/v)甲酸水溶液和0.1%(v/v)甲酸乙腈溶液梯度洗脱。以HLB C18为捕集柱,用0.1%(v/v)甲酸水溶液进行捕集和脱盐,采用正离子模式采集数据。对头孢噻吩钠中6个杂质进行了结构鉴定,对其来源进行了分析,并进一步确证了《中国药典》2010年版对头孢噻吩钠杂质A认定有误。采用本方法可以快速、简便、灵敏地对头孢噻吩钠杂质谱进行检测。 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献