Triterpenoid saponins from Symplocos chinensis have been investigated by positive ion electrospray ionization multi-stage tandem mass spectrometry (ESI-MS^n) in a new linear ion trap mass spectrometer. It has been fou...Triterpenoid saponins from Symplocos chinensis have been investigated by positive ion electrospray ionization multi-stage tandem mass spectrometry (ESI-MS^n) in a new linear ion trap mass spectrometer. It has been found that the fragmentation patterns of these given saponins significantly vary in accordance with different derivatization in the glucuronyl residue of oligosaccharide chains. The product ions show that the carboxyl group and the free hydroxyl group at the C-3' position of the glucuronyl residue are the key sites for determining the fragmentation pathways of these given triterpenoid saponins.The described results in this paper confirm the mechanisms previously postulated for cross-ring cleavage process for the metal coordinated species. Furthermore, the experimental results can benefit the determination of the minute compounds of this type in crude plant extracts and give some aid for the studies of similar glycoconjugates.展开更多
AchyranthosideI and Achyranthoside Ⅱ which were considered to be effective constituents from Achyranthes bientata BI were identified by electrospray tandem ionization mass spectrometric (ESI-MS^n) methods after macro...AchyranthosideI and Achyranthoside Ⅱ which were considered to be effective constituents from Achyranthes bientata BI were identified by electrospray tandem ionization mass spectrometric (ESI-MS^n) methods after macro-porous adsorbent chromatographic separation. Their characteristic mass spectra can be use as fingerprint for the identification of AchyranthosideI and Achyranthoside Ⅱ . This method is simple .,rapid and highly sensitive.展开更多
文摘Triterpenoid saponins from Symplocos chinensis have been investigated by positive ion electrospray ionization multi-stage tandem mass spectrometry (ESI-MS^n) in a new linear ion trap mass spectrometer. It has been found that the fragmentation patterns of these given saponins significantly vary in accordance with different derivatization in the glucuronyl residue of oligosaccharide chains. The product ions show that the carboxyl group and the free hydroxyl group at the C-3' position of the glucuronyl residue are the key sites for determining the fragmentation pathways of these given triterpenoid saponins.The described results in this paper confirm the mechanisms previously postulated for cross-ring cleavage process for the metal coordinated species. Furthermore, the experimental results can benefit the determination of the minute compounds of this type in crude plant extracts and give some aid for the studies of similar glycoconjugates.
文摘AchyranthosideI and Achyranthoside Ⅱ which were considered to be effective constituents from Achyranthes bientata BI were identified by electrospray tandem ionization mass spectrometric (ESI-MS^n) methods after macro-porous adsorbent chromatographic separation. Their characteristic mass spectra can be use as fingerprint for the identification of AchyranthosideI and Achyranthoside Ⅱ . This method is simple .,rapid and highly sensitive.
