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)�；瘜W(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： O6  關(guān)鍵詞： 3,4-Dihydropyrimidinone,Time-of-flight mass spectrometry,Electron impact  

【Studies on Fragmentation Regularity 】相關(guān)文章：

Chinese Studies Librarianship in North America04-27

Regularity of Keldys-Fichera Boundary Value Problem for Degenerate Elliptic Equations04-26

Bioremediation potential of spirulina: toxicity and biosorption studies of lead04-27

Studies on the Interaction of Beryllon Ш with Proteins by Voltammetric Technique and its Application04-27

Progress and review of the studies on the end-Triassic mass extinction event04-27

新學(xué)期的打算英語作文：A precise plan for my studies04-25

Comparative Embryological Studies on Infertility of Interspecific Hybridizations Between Oryza sativa with Different Plo04-26

Experimental studies on electrical breakdown field strength of electrode with water mist containing MC additives04-27

Why are There Indica Type and Japonica Type in Rice?-History of the Studies and a View for Origin of Two Types04-26

Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene04-26