Wavelength-Dependent Ultraviolet Photodissociation of Protonated Tryptamine
Wavelength-Dependent Ultraviolet Photodissociation of Protonated Tryptamine
复制标题
质子化色胺的波长依赖性紫外光解离
DOI：
10.1021/acs.jpca.0c02528
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发表时间：
2020
影响因子：
2.9
通讯作者：
Li Shuqi
中科院分区：
文献类型：
--
作者：
Zhang Kailin;Ma Lifu;Zhou Min;Shi Yingying;Li Shuqi
利用傅里叶变换离子回旋共振（FTICR）质谱仪和波长可调谐光参量振荡器（OPO）激光器，对质子化色胺（[Tryp+H]+）进行了紫外光解离（UVPD）实验。获得了不同激光波长下的UVPD质谱，观察到碎片离子产额与激光波长的关系。在210-310 nm范围内获得了[Tryp+H]+的UVPD光谱。除了先前报道的H损失和NH3损失两个竞争通道外，还观察到了CH 2NH和CH 2NH 2单元的两个重要损失通道，并通过UV-UV串联质谱和理论计算对其进行了进一步的研究。有趣的是，研究结果表明，CH 2NH损失和CH 2NH 2损失的竞争通道都是由ππ* 电子激发态引起的McLafferty重排.激发后，两种不同的解离途径分别产生两种不同的离子-中性络合物。在这项研究中显示的波长依赖性解离和现有的竞争通道反映了UVPD过程的多样性，这些有机分子。
Ultraviolet photodissociation (UVPD) experiments of protonated tryptamine ([Tryp+H]+) have been implemented by a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer combined with a wavelength-tunable optical parametric oscillator (OPO) laser. UVPD mass spectra under different laser wavelengths have been obtained, in which the dependence of the yield of fragment ions on the laser wavelength was observed. The UVPD spectrum of [Tryp+H]+has been obtained in the range of 210–310 nm. Besides the previously reported two competitive channels of H loss and NH3loss, two important channels of losing CH2NH and CH2NH2units were observed and further studied by UV–UV tandem mass spectrometry and theoretical calculations. Interestingly, results show that the pair of competitive channels of CH2NH loss and CH2NH2loss are both from the McLafferty-type rearrangement caused by ππ* electronic excited states. After the excitation, the two different dissociation pathways produce two different ion–neutral complexes, respectively. The wavelength-dependent dissociation and the existing competitive channels shown in this study reflect the diversity of UVPD processes of such organic molecules.