共查询到12条相似文献,搜索用时 0 毫秒
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本文报道12个合成的胞壁酰肽及其类似物的FABMS。所有化合物都出现质子化分子离子[M+H]^+和[M+Na]^+峰,碎片离子的形成主要是由MH^+脱水或脱保扩基,可以清晰地观察到序离子,另外由分子离子失去完整的吡喃糖可生成乳酸肽链离子。 相似文献
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本文采用表面沉淀进样技术,研究了九种四氟硼酸取代苯基重氮盐与18-冠醚-6和二苯并-24-冠醚-8形成络合物的FAB质谱,讨论了影响络合物稳定性的结构因素。 相似文献
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本文介绍用FABMS法或SIMS法研究抗生素柱晶白霉素、4″-酰螺旋霉素、Shengjimycins的质谱裂解规律。用MS数据和^13C NMR(COM,DEPT)数据鉴别该分子式和结构式。该方法有利于寻找新的抗生素。 相似文献
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α-cyano-ferulic acid(CFA)and 2,5-dihydroxybenzoic acid (DHB)were used as matrices to determine β-cyclodextrin, saccharide A from animal, saccharide B from plant an dextrans by MALDI-TOF-MS. The results showed that CAF could make some analytes desorbed and ionized more easliy and getting better reproducibility than DHB. 相似文献
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研究了硼酸三丙酯的摩擦表面在线强化性能.结果表明,硼酸三丙酯具有较好的摩擦表面在线强化功能;动态质谱分析给出了硼酸酯在摩擦界面发生的反应。 相似文献
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Phosphoramidates of nucleosides are continuing to be an important class of rationally designed therapeutics especially as oligonucleotide analogs employed as antisense and antigene agents. A series of different nucleoside 5'-thiophosphoramidates have recently been synthesized, their electrospray ionization mass specra have been investigated. The positive and negative electrospray ionization mass spectra all gave strong pseudomoleeular ions and characteristic fragment ions, however, they showed different fragmentation pathways. In the negative ion MS, the deprotonated molecule showed the base peak with loss of propylene. In the positive ion MS, the protonated molecule usually produced ions from loss of water, amino acid methyl ester, methyl alcohol, uridine and phosphoryl group. These mass spectral fragmentation pathways are helpful to determination of similarphosphoramidates of nucleosides. 相似文献
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