Studies On The Dissociation Mechanisms Of Organic Mass Spectrometry And Automatic Interpretation Method

This dissertation consists of four chapters. The first chapter reports the rapid analysis of trace impurities from synthetical medicine and analysis of the chemical constitutents from Chinese herb medicines. The second chapter elaborates the studies on the discorvery and synthesis of new type of Pd Pincer catalyst by using MS and tandem MS together with the testing of its catalyst activity. The third chapter dwells on the designation and development of automatic tandem mass spectrometry analysis software. The last chapter presents a review on the dissociation technique of mass spectrometry.The first chapter reports the rapid analysis of trace impurities from synthesis medicine and analysis of the chemical constitutents from Chinese herb medicines. The fission mechanism of 5-bromotetrandrine was obtained by analysis of the dissociation pathways of major product, by using which the possible structure of the two trace impurties was assumed. There are lots of saponins in Sapindus mukurossi. Except for the good spumescence and decontamination, it possesses the bioactivity of antigen and antitch. First of all, the high resolution mass information was obtained by ESI-QTOF. Hence the possible molecular formulars were acquired too. Then we conducted the further detection of the structures of its saponins by using ESI-IT technology. In the same manner, first the molecular formulars of every constituent from Dioscorea panthaica in total saponins were obtained by ESI-QTOF, and then acquired the fission mechanism of this type of compounds by tandem mass experiment on a series of known and available saponins. In the same time, the analysis flowchart was concluded. Here the relationship between the ion intensity and the corresponding dissiociation activation energy was studied by computer chemistry. Then the four pairs of isomers were differentiated by APCI-MS/MS, as well as the characterization of known and unknown compounds. The assumption was confirmed by HPLC-MS/MS. Among them the possible structures of four unknown saponins was presented.The second part was discovery and synthesis of a new type of Pd pincer catalyst by MS and tandem MS. The coupling reaction catalyzed by Pd is the most effective method in C-C formation in organic synthesis. Apart from that, thiourea is type of compounds that are stable to atmosphere and moisture. Hence we designed a series of Pd thiourea catalysts. Some of them show the excellent catalyst activity. The abnormal parent ion [M-H]~+ was founded in positive ESI mode when we conduct some mass spectrometry experiments on the bicyclical thiourea Pd complex. The structure was proposed by mass and tandem mass spectrometry. Because it was a new type of pincer, we want to test its catalyst activity. So the Pd pincer was synthesized and the detail structure was obtained by x-ray experiment. It shows the more fitness in catalysis of Suzuki reaction by comparison with the analogue.The third chapter dwells on the design and development of automatic tandem mass spectrometry analysis software. Inspired by the former two chapters, the AuMass (version 1.0) was developed. Its algorithm is: first check the diagnostic ion, diagnostic neutral loss or diagnostic ions mass intervals in database to find out what the analyst's skeleton belongs to, then identify the peripheral functional group by the corresponding analysis flowchart. The chemical constituents of Paeonia lactiflora were identified rapidly by using AuMass. To increase the analysis ability, the other types of compounds from Chinese herbs was concluded. Actually, the software is proven to have the much valuable application.The last chapter presented the review on the some kinds of fission technique of mass spectrometry. It involves the collision induced dissociation (CID), laser induced dissociation (LID), electron capture dissociation/electron transfer dissociation (ECD/ETD), infrared multiple photons dissiociation, black body irradition dissociation and PQD fission technique from Finnigan.