Mass spectrometric analyses of biologically active choline phospholipids and their lyso derivatives.
作者:AKIRA TOKUMURA、YASOMI HANDA、YASUKO YOSHIOKA、HIROAKI TSUKATANI
DOI:10.1248/cpb.31.4425
日期:——
The electron impact and chemical ionization mass spectra of 1-O-hexadecyl- and 1-palmitoyl-2-O-acetyl-sn-glycero-3-phosphocholines and their lyso derivatives were measured by insertion of the compounds into a direct inlet system. The lysophospholipids were decomposed by heating at over 300°C into multiple compounds that volatilized together and gave several characteristic ion peaks when subjected to electron impact or interaction with an ion plasma of reactant gas. The mass spectral data indicated that the major pyrolysis products of these lysophospholipids were produced by elimination of methanol or N, N-dimethylethanolamine. When sn-2-acetyl phospholipids were introduced on the direct insertion probe and heated, several pyrolysis products volatilized together at above 350°C. The results suggested the major pyrolysis mechanism was loss of the phosphorylcholine moiety, together with some deacetylation and subsequent elimination of methanol and N, N-dimethylethanolamine from the sn-2-acetyl phospholipids.
通过将 1-O-十六烷基和 1-棕榈酰基-2-O-乙酰基-sn-甘油-3-磷脂及其溶血磷脂衍生物插入直接进样系统,测量了这些化合物的电子碰撞和化学电离质谱。溶血磷脂在超过 300°C 的温度下加热分解成多种化合物,这些化合物一起挥发,并在受到电子撞击或与反应气体离子等离子体相互作用时产生多个特征离子峰。质谱数据表明,这些溶血磷脂的主要热解产物是通过消除甲醇或 N,N-二甲基乙醇胺产生的。在直接插入探针上引入 sn-2 乙酰基磷脂并加热时,几种热解产物在 350°C 以上一起挥发。结果表明,热解的主要机制是磷酰胆碱分子的损失,以及一些脱乙酰化作用,随后 Sn-2 乙酰基磷脂中的甲醇和 N,N-二甲基乙醇胺被消除。