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Jianguo Zeng - One of the best experts on this subject based on the ideXlab platform.

  • systematic identification of alkaloids in macleaya microcarpa fruits by liquid chromatography tandem mass spectrometry combined with the isoquinoline alkaloids biosynthetic pathway
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Zhixing Qing, Pi Cheng, Xiubin Liu, Yisong Liu, Jianguo Zeng
    Abstract:

    Abstract Alkaloids in Macleaya microcarpa were characterized systematically by combining liquid chromatography tandem mass spectrometry (LC–MS/MS) with the biosynthetic pathway of isoquinoline alkaloids. The mass spectral fragmentation behaviors of 16 references belonging to eight types of alkaloids that exist in the biosynthetic pathway of isoquinoline were investigated in detail. The Benzyltetrahydroisoquinoline and aporphine alkaloids were distinguished by characteristic losses of the NHR 1 R 2 (R 1 and R 2 represent the substituent groups of the nitrogen atom) radical and the fragment ions below m / z 200. Tetrahydroprotoberberine, N -methyltetrahydroberberine and protopine alkaloids were differentiated by the retro-Diels–Alder (RDA) reaction, α-cleavage and the [M–H 2 O] + and [M–CH 4 ] + ions. Discrimination of protoberberine, benzophenanthridine and dihydrobenzophenanthridine-type alkaloids can be realized through the characteristic [fragment ion-2H] + , [M–H 2 O] + , [M–CH 4 ] + , [M+H–CH 3 CH 2 CH 2 OH] + and [M+H–CH 3 COCH 3 ] + ions. Forty-one alkaloids, including one Benzyltetrahydroisoquinoline, one aporphine, nine protopines, seven protoberberines, one tetrahydroprotoberberine, three N -methyltetrahydroprotoberberines, five benzophenanthridines and fourteen dihydrobenzophenanthridines, were separated and identified simultaneously. Thirty-three of these were reported for the first time in M. microcarpa . The Benzyltetrahydroisoquinoline, aporphine, tetrahydroprotoberberine and N -methyltetrahydroprotoberberine-type alkaloids have not been reported previously in M. microcarpa . This method can be applied to the analysis of herbal medicines that possess the biosynthetic pathway of isoquinoline alkaloids.

  • structural speculation and identification of alkaloids in macleaya cordata fruits by high performance liquid chromatography quadrupole time of flight mass spectrometry combined with a screening procedure
    Rapid Communications in Mass Spectrometry, 2014
    Co-Authors: Zhixing Qing, Pi Cheng, Xiubin Liu, Yisong Liu, Jianguo Zeng, Wei Wang
    Abstract:

    RATIONALE Alkaloids with significant therapeutic effects are the main active constituents of Macleaya cordata, which is a perennial herb plant in the Papaveraceae family. A systematic and novel method for speculating and identifying the structures of alkaloids in M. cordata fruits by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/Q-TOF-MS) with a screening procedure was reported. METHODS Investigation of mass spectral fragmentation of alkaloids was carried out based on the tandem mass spectrometry (MS/MS) data analyses of eight reference substances. The skeletons of alkaloids were determined by their ultraviolet spectra (UV) and MS/MS data. The substituent groups of the alkaloids were acquired through a screening procedure developed in our laboratory and MS/MS data. The substituent linkage sites were deduced by MS/MS fragmentation behavior, as well as biosynthetic pathways of related alkaloids. RESULTS The structures of 21 alkaloids were speculated in this study, 10 of which were reported for the first time in M. cordata. Furthermore, Benzyltetrahydroisoquinoline and N-methyltetrahydroprotoberberine-type alkaloids were discovered, which indirectly proved that the biosynthetic pathways of benzophenanthridine alkaloids reported in Eschscholtzia california existed in M. cordata as well. CONCLUSIONS HPLC/Q-TOF-MS combined with a screening procedure was a systematic and reliable method for speculating and elucidating the structures of alkaloids. This study might be useful for the identification of other compounds in herbal medicines.

Zbigniew Czarnocki - One of the best experts on this subject based on the ideXlab platform.

Zhixing Qing - One of the best experts on this subject based on the ideXlab platform.

  • systematic identification of alkaloids in macleaya microcarpa fruits by liquid chromatography tandem mass spectrometry combined with the isoquinoline alkaloids biosynthetic pathway
    Journal of Pharmaceutical and Biomedical Analysis, 2015
    Co-Authors: Zhixing Qing, Pi Cheng, Xiubin Liu, Yisong Liu, Jianguo Zeng
    Abstract:

    Abstract Alkaloids in Macleaya microcarpa were characterized systematically by combining liquid chromatography tandem mass spectrometry (LC–MS/MS) with the biosynthetic pathway of isoquinoline alkaloids. The mass spectral fragmentation behaviors of 16 references belonging to eight types of alkaloids that exist in the biosynthetic pathway of isoquinoline were investigated in detail. The Benzyltetrahydroisoquinoline and aporphine alkaloids were distinguished by characteristic losses of the NHR 1 R 2 (R 1 and R 2 represent the substituent groups of the nitrogen atom) radical and the fragment ions below m / z 200. Tetrahydroprotoberberine, N -methyltetrahydroberberine and protopine alkaloids were differentiated by the retro-Diels–Alder (RDA) reaction, α-cleavage and the [M–H 2 O] + and [M–CH 4 ] + ions. Discrimination of protoberberine, benzophenanthridine and dihydrobenzophenanthridine-type alkaloids can be realized through the characteristic [fragment ion-2H] + , [M–H 2 O] + , [M–CH 4 ] + , [M+H–CH 3 CH 2 CH 2 OH] + and [M+H–CH 3 COCH 3 ] + ions. Forty-one alkaloids, including one Benzyltetrahydroisoquinoline, one aporphine, nine protopines, seven protoberberines, one tetrahydroprotoberberine, three N -methyltetrahydroprotoberberines, five benzophenanthridines and fourteen dihydrobenzophenanthridines, were separated and identified simultaneously. Thirty-three of these were reported for the first time in M. microcarpa . The Benzyltetrahydroisoquinoline, aporphine, tetrahydroprotoberberine and N -methyltetrahydroprotoberberine-type alkaloids have not been reported previously in M. microcarpa . This method can be applied to the analysis of herbal medicines that possess the biosynthetic pathway of isoquinoline alkaloids.

  • structural speculation and identification of alkaloids in macleaya cordata fruits by high performance liquid chromatography quadrupole time of flight mass spectrometry combined with a screening procedure
    Rapid Communications in Mass Spectrometry, 2014
    Co-Authors: Zhixing Qing, Pi Cheng, Xiubin Liu, Yisong Liu, Jianguo Zeng, Wei Wang
    Abstract:

    RATIONALE Alkaloids with significant therapeutic effects are the main active constituents of Macleaya cordata, which is a perennial herb plant in the Papaveraceae family. A systematic and novel method for speculating and identifying the structures of alkaloids in M. cordata fruits by high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry (HPLC/Q-TOF-MS) with a screening procedure was reported. METHODS Investigation of mass spectral fragmentation of alkaloids was carried out based on the tandem mass spectrometry (MS/MS) data analyses of eight reference substances. The skeletons of alkaloids were determined by their ultraviolet spectra (UV) and MS/MS data. The substituent groups of the alkaloids were acquired through a screening procedure developed in our laboratory and MS/MS data. The substituent linkage sites were deduced by MS/MS fragmentation behavior, as well as biosynthetic pathways of related alkaloids. RESULTS The structures of 21 alkaloids were speculated in this study, 10 of which were reported for the first time in M. cordata. Furthermore, Benzyltetrahydroisoquinoline and N-methyltetrahydroprotoberberine-type alkaloids were discovered, which indirectly proved that the biosynthetic pathways of benzophenanthridine alkaloids reported in Eschscholtzia california existed in M. cordata as well. CONCLUSIONS HPLC/Q-TOF-MS combined with a screening procedure was a systematic and reliable method for speculating and elucidating the structures of alkaloids. This study might be useful for the identification of other compounds in herbal medicines.

Anna Zawadzka - One of the best experts on this subject based on the ideXlab platform.

Cingolani G.m. - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and preliminary pharmacological evaluation of 5-hydroxy- and 5,6-dihydroxy-1,2,3,7,12a-hexahydrobenzo[5,6]cyclohepta[1,2,3-ij]isoquinoline dervatives as dopamine receptor ligands
    2001
    Co-Authors: Cingolani G.m., Di Stefano A., Napolitani F., Mosciatti B., Giorgioni G., Cinone N., Brunetti L., Luisi G., Michelotto B., Costa B.
    Abstract:

    A series of 5-hydroxy- and 5,6-dihydroxy-1,2,3,7,12,12a-hexahydrobenzo[5,6]cyclohepta[1,2,3-ij]isoquinoline derivatives (5a--e and 6a--e) were synthesized as conformationally rigid analogues of 1-Benzyltetrahydroisoquinoline and evaluated for their affinity at D(1) and D(2) dopamine receptors. All compounds showed lower D(1) and D(2) affinities than dopamine. The 5-hydroxy-1-methyl-2,3,12,12a-hexahydrobenzo[5,6]cyclohepta[1,2,3-ij]isoquinoline 5a and the 5,6-dihydroxy analogue 6a showed D(2) agonist activity. This was proved by their effects on prolactin release from primary cultures of rat anterior pituitary cells. Molecular modeling studies showed that the geometric parameters (namely the distances from meta and para hydroxyl oxygens to the nitrogen and the height of nitrogen from the hydroxylated phenyl ring plane) of the dopaminergic pharmacophore embedded in our compounds have lower values in comparison with those observed in D(1) and D(2) selective ligands

  • Synthesis and preliminary pharmacological evaluation of 5-hydroxy-and 5,6-dihydroxy-1,2,3,7,12,12a-hexahydrobenzo [5,6]cycloheptal [1,2,3-ij]isoquinoline derivatives as dopamine receptor ligands
    'Elsevier BV', 2001
    Co-Authors: Cingolani G.m., Di Stefano A., Mosciatti B., Giorgioni G., Cinone N., Brunetti L., Luisi G., Michelotto B., Napoletani F., Orlando G.
    Abstract:

    A series of 5-hydroxy- and 5,6-dihydroxy- 1,2,3,7,12,12a-hexahydrobenzo[5,6]cyclohepta[1,2,3-iJ]isoquinoline derivatives (5a-e and 6a-e) were synthesized as conformationally rigid analogues of 1-Benzyltetrahydroisoquinoline and evaluated for their affinity at D-1 and D-2 dopamine receptors. All compounds showed lower D1 and D affinities than dopamine. The 5-hydroxy-1-methyl-2,3,12,12a-hexahydrobenzo[5,6]cyclohepta[1,2,3-ij] 5a and the 5,6dihydroxy analogue 6a showed D-2 agonist activity. This was proved by their effects on prolactin release from primary cultures of rat anterior pituitary cells. Molecular modeling studies showed that the geometric parameters (namely the distances from meta and para hydroxyl oxygens to the nitrogen and the height of nitrogen from the hydroxylated phenyl ring plane) of the dopaminergic pharmacophore embedded in our compounds have lower values in comparison with those observed in D-1 and D-2 selective ligands. (C) 2001 Elsevier Science Ltd. All rights reserved