Studies on Fragmentation Regularity of 5-Methoxycarbonyl-4-substituted-6-methyl-3,4-dihydropyrimidin-2(1H)-ones by Time-

The electron impact time-of-flight(TOF) mass spectra of the title compounds were studied to establish their fragmentation processes. With the high resolution of the TOF instrument, the exact mass for each fragment was determined. These data were used to infer the molecular formulas and the elemental compositions for all the molecular ions and fragments through software interpretation. By further applying the fragmentation regularity, the majority of ions were fully assigned. The main fragmentation pathways of the title compounds include the formation of molecular ions by the loss of R1 groups in the 4-position and the ester groups in the 5-position. The formed ion can be further fragmented by the elimination of MeOH.

作 者： LI Qian-Rong SALEHI Hojatollah YIN Hao Qing-xiang   作者單位： LI Qian-Rong,YIN Hao(Structure Research Laboratory)

SALEHI Hojatollah(Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China;Scholarship Department, Ministry of Science, Research and Technology, P. O. Box 15875-6186, Tehran, Iran)

Qing-xiang(Department of Chemistry, University of Science and Technology of China, Hefei 230026, P. R. China) 

刊 名： 高等學(xué)校化學(xué)研究（英文版）  ISTIC SCI 英文刊名： CHEMICAL RESEARCH IN CHINESE UNIVERSITIES  年，卷(期)： 2004 20(6)  分類號(hào)： O6  關(guān)鍵詞： 3,4-Dihydropyrimidinone,Time-of-flight mass spectrometry,Electron impact  

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