NEGATIVE ION CHEMICAL IONIZATION MASS SPECTROMETRY OF PERFLUOROACYL DERIVATIVES

全氟酰基衍生物的负离子化学电离质谱法

• 批准号: 6665790
• 负责人: FONG-FU HSU
• 金额: $ 15.75万
• 依托单位: WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2003-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6665790
• 关键词: biological products; biomedical resource; musculoskeletal system; proteins; spectrometry

The negative ion chemical ionization (NCI) mass spectra of the pentafluoroproprionyl (PFP) and heptafluorobutyryl (HFB) derivatives of 2-aminophenol contain a base ion which is generated by a mechanism involving the a loss of 44 amu, and ions reflecting this loss are also observed in the NCI spectra of the PFP or HFB derivatives of other ortho hydroxyanilines, including 3-hydroxybenzidine and the n-propyl esters of 2-hydroxyanilinic acid and 2-aminotyrosine. A corresponding ion is not observed in the NCI spectra of the trifluoroacetyl (TFA) derivative of 2-aminophenol or in the spectra of the PFP or HFB derivatives of meta or para isomers of hydroxyaniline or of 2-ethylaminophenol. Examination of the mechanism of this loss by tandem mass spectrometry, linked scanning, and high resolution mass spectrometry revealed that it reflects elimination of CO2 and indicate that the fragmentation pathway involves an initial loss of HF, in which the hydrogen atom is derived from the deriv atized amide nitrogen, followed by formation of a ring intermediate from which CO2 is subsequently eliminated to yield another ring structure. An ion generated by loss of 44 amu is also observed in the NCI spectra of HFB or PFP derivatives of catechols, including L-dopa and catechol itself, and the mechanism of this loss may also involve formation of a ring intermediate from which CO2 is subsequently eliminated. The occurrence of this loss of CO2 can be used to achieve distinction among regio-isomers of hydoxyanilines and to distinguish a catechol from a resorcinol or hydroquinone nucleus.

负离子化学电离 (NCI) 质谱 五氟丙酰基 (PFP​​) 和七氟丁酰基 (HFB) 衍生物 2-氨基苯酚含有一个碱离子，该离子是通过某种机制产生的 涉及 44 amu 的损失，反映这种损失的离子也 在其他 PFP 或 HFB 衍生物的 NCI 光谱中观察到 邻羟基苯胺，包括3-羟基联苯胺和正丙基 2-羟基苯胺酸和2-氨基酪氨酸的酯。 对应的一个 在三氟乙酰基 (TFA) 的 NCI 光谱中未观察到离子 2-氨基苯酚的衍生物或在 PFP 或 HFB 的光谱中 羟基苯胺的间位或对位异构体的衍生物 2-乙基氨基苯酚。 通过以下方式检查这种损失的机制 串联质谱、联动扫描和高分辨率质量 光谱分析表明它反映了 CO2 的消除并表明 碎裂途径涉及 HF 的初始损失， 氢原子源自哪个 衍生化酰胺氮，然后形成环 随后消除 CO2 的中间体，得到 另一个环状结构。 失去 44 amu 所产生的离子也 在儿茶酚的 HFB 或 PFP 衍生物的 NCI 光谱中观察到， 包括左旋多巴和儿茶酚本身，以及这种损失的机制 还可能涉及形成环中间体，CO2 从中产生 随后被淘汰。 CO2 损失的发生可以是 用于区分羟基苯胺的区域异构体和 区分儿茶酚和间苯二酚或氢醌核。