In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of r...In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of raceanisodamine was crazed and characteristic ions m/z261 and base peak m/z94 were produced by losing free group CH2CH2OH, then its alcoholysis can create some ploy-ring ions such as m/z140 and m/z 156. These fragment act as the characters of raceanisodamine.展开更多
The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of mel...The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of melatonin are much more than quasimolecular ions. The fragmentation pathways of melatonin were also discussed.展开更多
The mass spectrometric behaviour of five 3 -methyl-la-phenyl - 1, 1 -dichloro- la. 2,3,4- tetrahydro-azirino[2, 1 -q][1,5]benzothiazepines has been studied with The aid of mass-analysed ion kinetic energy spectrometry...The mass spectrometric behaviour of five 3 -methyl-la-phenyl - 1, 1 -dichloro- la. 2,3,4- tetrahydro-azirino[2, 1 -q][1,5]benzothiazepines has been studied with The aid of mass-analysed ion kinetic energy spectrometry. All compounds show a tendency to eliminate a chlorine atom from aziridine ring, and Then eliminate a neutral propene from The thiazepine ring to yield l,4-benzothiazine ions, or furTher eliminate a chlorine to yield 1,6-benzothiazocine ions. They could also eliminate consecutively a chlorine atom and hydrogen chloride in The samle time to undergo a ring enlargement rearrangement to yield 1,6-benzothiazocine ions, which furTher lose small molecular fragments or propyne and undergo rearrangement to give 1,4- benzothiazine ions.展开更多
Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of...Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of m/z 143. The main fragments are from the α cleavage and its rearranging ones at the carbonyl gronp.展开更多
Electron impact ionization mass spectra of six new synthetic bis-piperazinium salts (M2+ 2Br-2HC1) with anti-tumor activities were obtained. Although the M+ ions and double charge ions M2+ were notobserved in E1 mass ...Electron impact ionization mass spectra of six new synthetic bis-piperazinium salts (M2+ 2Br-2HC1) with anti-tumor activities were obtained. Although the M+ ions and double charge ions M2+ were notobserved in E1 mass spectra, some strange ions such as [M-2]+ ions,[M-R]+ ions , [M-R-l]+ ions, [M-2R]+ ions and even [RX]+ ions presented in EIMS by decreasing the electron energy. These phenomena may be explained as R+ rearrangement and intermolecular reaction occurring in the condensed phase. We tried to describe the main routes of fragmentation and high sensitive mass spectra of the fragments oaboutthese compounds.展开更多
文摘In this paper, raceanisodamine are analyzed by El mass spectrometry(EIMS),their characteristic fragment ions were obtained. The fragmentation mechanism on this component was discussed. The results showed the ring of raceanisodamine was crazed and characteristic ions m/z261 and base peak m/z94 were produced by losing free group CH2CH2OH, then its alcoholysis can create some ploy-ring ions such as m/z140 and m/z 156. These fragment act as the characters of raceanisodamine.
文摘The electron impact mass spectra behavior of melatonin were studied by mass spectrometry through the separation of the pill, extracting of the effective part. The detecting results showed that the fragment ions of melatonin are much more than quasimolecular ions. The fragmentation pathways of melatonin were also discussed.
文摘The mass spectrometric behaviour of five 3 -methyl-la-phenyl - 1, 1 -dichloro- la. 2,3,4- tetrahydro-azirino[2, 1 -q][1,5]benzothiazepines has been studied with The aid of mass-analysed ion kinetic energy spectrometry. All compounds show a tendency to eliminate a chlorine atom from aziridine ring, and Then eliminate a neutral propene from The thiazepine ring to yield l,4-benzothiazine ions, or furTher eliminate a chlorine to yield 1,6-benzothiazocine ions. They could also eliminate consecutively a chlorine atom and hydrogen chloride in The samle time to undergo a ring enlargement rearrangement to yield 1,6-benzothiazocine ions, which furTher lose small molecular fragments or propyne and undergo rearrangement to give 1,4- benzothiazine ions.
文摘Notable features of EIMS cleavage for eight N,N diacyl adipyl dihydrazides are summarized. The sources and chemical structures of the main fragments are interpreted. All of the eight compounds give the base peak of m/z 143. The main fragments are from the α cleavage and its rearranging ones at the carbonyl gronp.
文摘Electron impact ionization mass spectra of six new synthetic bis-piperazinium salts (M2+ 2Br-2HC1) with anti-tumor activities were obtained. Although the M+ ions and double charge ions M2+ were notobserved in E1 mass spectra, some strange ions such as [M-2]+ ions,[M-R]+ ions , [M-R-l]+ ions, [M-2R]+ ions and even [RX]+ ions presented in EIMS by decreasing the electron energy. These phenomena may be explained as R+ rearrangement and intermolecular reaction occurring in the condensed phase. We tried to describe the main routes of fragmentation and high sensitive mass spectra of the fragments oaboutthese compounds.
