The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.div...The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.divaricata leaf,with relative molecular weight of 335 and 365,respectively and lower content.The constituent with relative molecular weight 335 is a retronecine-type alkaloid,and identified as integerrimine;another constituent with relative molecular weight 365 is an otonecine-type alkaloid,speculated to be isomer of usaramine or 18-hydroxyinterrimine.展开更多
Forced degradation study of argatroban under conditions of hydrolysis(neutral, acidic and alkaline), oxidation,photolysis and thermal stress, as suggested in the ICH Q1 A(R2), was accomplished. The drug showed signifi...Forced degradation study of argatroban under conditions of hydrolysis(neutral, acidic and alkaline), oxidation,photolysis and thermal stress, as suggested in the ICH Q1 A(R2), was accomplished. The drug showed significant degradation under hydrolysis(acidic, alkaline) and oxidation(peroxide stress) conditions. The drug remained stable under thermal and photolytic stress conditions. In total, seven novel degradation products(DP-1 to DP-7) were found under diverse conditions, which were not reported earlier. The chemical structures of these degradation products were characterized by ~1H NMR,^(13)C NMR, 2 D NMR, Q-TOF-MSnand IR spectral analysis and the proposed degradation products structures were further confirmed by the individual synthesis.展开更多
N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are imp...N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are important markers of chemical warfare agents because they are structurally relative to both nerve agents and N-mustards. In this study, fragmentation pathways of the most characteristic fragment ions in Q-TOF mass spectrometry were proposed based on the information from accurate mass and secondary fragmentations of product ions scan experiments. Results indicated that the base ion in LC/HRMS was the quasi-molecular ion [M+H]+. In LC-HRMS/MS, it was [M+H-CnH2n+1P(O)(OH)CmH2m+1O]+ fragment ion which was formed by losing an alkyloxy alkylphosphoryloxy group from the quasi-molecular ion. The diagnostic ion m/z84.0814 was identified as [C5H10N]+, which was the group of (CH2=CH)2N+(H)CH3. PNPs have two protonated centers. One is on the N atom, the other is on the O atom (P=O). O-n-propyl PNPs generally exhibited two fragmentation pathways. Firstly, the quasi-molecular ion [M+H]+ lost a propoxy alkylphosphoryloxy group to produce [R1P(OH+)(O-n-C3H7)OCH2CH2N(CH3)CH=CH2]+, which could be fragmented further to produce [C5H10N]+ ion. Secondly, [R1P(OH+)(O-n-C3H7) OCH=CH2]+ ions were produced from [M+H]+ and fragmented further to produce the abundant ions [R1P(OH+)(OH)OCH =CH2]. However, O-isopropyl PNPs characteristically produced weak fragment ions [M+H-C3H6]+, which were presumably formed via loss of CH3CH=CH2 from [M+H]+. Other PNPs showed similar fragmentation pathways as O-n-propyl PNPs. On the summarization of the MS fragmentation pathways of PNPs, LC-HRMS/MS quantitative and qualitative methods were developed and applied to analyze N-Methyl bis(2-(butoxy-methylphosphoryloxy)ethyl]amine in high background organic samples. The analytical results had successfully supported the sample preparation for the 33rd official proficiency test of Organization for Prohibition of Chemical Weapons (OPCW).展开更多
Inosiplex is a compound formulation composed of inosine and p-acetaminobenzoic acid （PABA） salt of N,N-dimethylamino-2-propanol （DIP）. This study was to investigate the clinical plasma pharmacokiuetic properties o...Inosiplex is a compound formulation composed of inosine and p-acetaminobenzoic acid （PABA） salt of N,N-dimethylamino-2-propanol （DIP）. This study was to investigate the clinical plasma pharmacokiuetic properties of DIP and PABA after single and multiple oral doses of inosiplex tablets in healthy Chinese volunteers. The established LC/MS/MS method for plasma DIP determination had a linear range of 0.02-10 pg/mL, and the HPLC method for plasma PABA determination had a linear range of 0.0540 pg/mL. Linear pharmacokinetic characteristics were found with single oral doses of 0.5, 1.0 and 2.0 g. No obvious accumulation effects were observed for DIP and PABA.展开更多
文摘The pyrrolizidine alkaloids(PAs) in leaf of Gynura divaricata(L.) DC.was analyzed by LC-MSn technique.The result shows that two hepatotoxic pyrrolizidine alkaloids(HPAs) are detected from the methanol extract of G.divaricata leaf,with relative molecular weight of 335 and 365,respectively and lower content.The constituent with relative molecular weight 335 is a retronecine-type alkaloid,and identified as integerrimine;another constituent with relative molecular weight 365 is an otonecine-type alkaloid,speculated to be isomer of usaramine or 18-hydroxyinterrimine.
基金Scholarship for Stabilizing Tablent from Hunan Agricultural University (05WD11)Scholarslip for Excellent Youthfrom Hunan Education Department (07B035)
文摘Forced degradation study of argatroban under conditions of hydrolysis(neutral, acidic and alkaline), oxidation,photolysis and thermal stress, as suggested in the ICH Q1 A(R2), was accomplished. The drug showed significant degradation under hydrolysis(acidic, alkaline) and oxidation(peroxide stress) conditions. The drug remained stable under thermal and photolytic stress conditions. In total, seven novel degradation products(DP-1 to DP-7) were found under diverse conditions, which were not reported earlier. The chemical structures of these degradation products were characterized by ~1H NMR,^(13)C NMR, 2 D NMR, Q-TOF-MSnand IR spectral analysis and the proposed degradation products structures were further confirmed by the individual synthesis.
文摘N-Methyl bis(2-(alkyloxy-alkylphosphoryloxy)ethyl)amines, which are abbreviated as PNPs, are a series of new skeleton chemicals belonging to schedule 2.B.04 chemicals of Chemical Weapons Convention (CWC). PNPs are important markers of chemical warfare agents because they are structurally relative to both nerve agents and N-mustards. In this study, fragmentation pathways of the most characteristic fragment ions in Q-TOF mass spectrometry were proposed based on the information from accurate mass and secondary fragmentations of product ions scan experiments. Results indicated that the base ion in LC/HRMS was the quasi-molecular ion [M+H]+. In LC-HRMS/MS, it was [M+H-CnH2n+1P(O)(OH)CmH2m+1O]+ fragment ion which was formed by losing an alkyloxy alkylphosphoryloxy group from the quasi-molecular ion. The diagnostic ion m/z84.0814 was identified as [C5H10N]+, which was the group of (CH2=CH)2N+(H)CH3. PNPs have two protonated centers. One is on the N atom, the other is on the O atom (P=O). O-n-propyl PNPs generally exhibited two fragmentation pathways. Firstly, the quasi-molecular ion [M+H]+ lost a propoxy alkylphosphoryloxy group to produce [R1P(OH+)(O-n-C3H7)OCH2CH2N(CH3)CH=CH2]+, which could be fragmented further to produce [C5H10N]+ ion. Secondly, [R1P(OH+)(O-n-C3H7) OCH=CH2]+ ions were produced from [M+H]+ and fragmented further to produce the abundant ions [R1P(OH+)(OH)OCH =CH2]. However, O-isopropyl PNPs characteristically produced weak fragment ions [M+H-C3H6]+, which were presumably formed via loss of CH3CH=CH2 from [M+H]+. Other PNPs showed similar fragmentation pathways as O-n-propyl PNPs. On the summarization of the MS fragmentation pathways of PNPs, LC-HRMS/MS quantitative and qualitative methods were developed and applied to analyze N-Methyl bis(2-(butoxy-methylphosphoryloxy)ethyl]amine in high background organic samples. The analytical results had successfully supported the sample preparation for the 33rd official proficiency test of Organization for Prohibition of Chemical Weapons (OPCW).
基金financially supported by the Fundamental Research Funds for the Central Universities(Grant no.JKP2011008)the Qing Lan Project,and the Program for New Century ExcellentTalents in University(Grant no.NCET-10-0816)
文摘Inosiplex is a compound formulation composed of inosine and p-acetaminobenzoic acid （PABA） salt of N,N-dimethylamino-2-propanol （DIP）. This study was to investigate the clinical plasma pharmacokiuetic properties of DIP and PABA after single and multiple oral doses of inosiplex tablets in healthy Chinese volunteers. The established LC/MS/MS method for plasma DIP determination had a linear range of 0.02-10 pg/mL, and the HPLC method for plasma PABA determination had a linear range of 0.0540 pg/mL. Linear pharmacokinetic characteristics were found with single oral doses of 0.5, 1.0 and 2.0 g. No obvious accumulation effects were observed for DIP and PABA.
