The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Dean Guo - One of the best experts on this subject based on the ideXlab platform.
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metabolic pathway and metabolites of total diterpene acid isolated from Pseudolarix kaempferi
Acta pharmaceutica Sinica, 2014Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Shifeng Sun, Dean GuoAbstract:The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.
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characterization of diterpenoids in the bark of Pseudolarix kaempferi by hplc esi msn
Acta pharmaceutica Sinica, 2011Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Jian Han, Jie Kang, Baorong Wang, Dean GuoAbstract:Fragmentation behavior of diterpenoids was investigated by ESI/MS n and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry (HPLC-ESI/MS n ). The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C 4-O bond. Furthermore, the eliminations of substituent groups at C-18, C-7 and C-8 can also be observed in the MS n (n = 3−4) spectra. For C-4 acetoxy subsititued diterpenoids, (M+Na−60) + and (M−H−104)
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simultaneous determination of seven major diterpenoids in Pseudolarix kaempferi by high performance liquid chromatography dad method
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Yuxin Sheng, Weixing Wang, Suxiu Feng, Fei Cheng, Dean GuoAbstract:A reversed phase high-performance liquid chromatography method was established for the first time to simultaneously qualify the seven major diterpenoids in Pseudolarix kaempferi, namely pseudolaric acid B O-beta-D-glucopyranoside (1), pseudolaric acid C2 (2), pseudolaric acid C1 (3), deacetylpseudolaric acid A (4), pseudolaric acid A O-beta-D-glucopyranoside (5), pseudolaric acid B (6) and pseudolaric acid A (7). The optimal conditions of separation and detection were achieved on an Inertsil ODS-3 column with gradient elution of methanol and 0.5% aqueous acetic acid (v/v) at the flow rate of 0.6 ml min(-1) within 40 min and detection wavelength set at 262 nm. All calibration curves showed good linear regression (r2>0.9999) within test ranges. This method provided good accuracy with recoveries in the range of 94.3-106.1% and good precision with R.S.D.s of repeatability and intermediate precision less than 0.57% and 4.67%, respectively. The method was successfully applied to qualitative and quantitative determination of 20 P. kaempferi among the 54 samples collected from different areas. The results revealed that the commercial crude drugs were seriously confused and the developed HPLC assay could be used as a suitable qualitative and quantitative determination method for P. kaempferi.
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cytotoxic diterpenoids from the bark of Pseudolarix kaempferi and their structure activity relationships
Journal of Natural Products, 2007Co-Authors: Peng Liu, Hongzhu Guo, Weixing Wang, Jie Zhang, Jian Han, Jianping Zhou, Tong Zhang, Zhenming Liu, Dean GuoAbstract:Four new diterpenoids, 11S-deacetylpseudolaric acid A (2), deacetylpseudolaric acid A O-beta-d-glucopyranoside (3), deacetylpseudolaric acid A 2,3-dihydroxypropyl ester (4), and deacetylpseudolaric acid B 2,3-dihydroxypropyl ester (5), and nine known diterpenoids were isolated from the bark of Pseudolarix kaempferi. Their structures were determined on the basis of chemical and spectroscopic analyses. In addition, their in vitro cytotoxic activities against three human cancer cell lines and their structure-activity relationships were evaluated.
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Simultaneous determination of seven major diterpenoids in Pseudolarix kaempferi by high-performance liquid chromatography DAD method
药学与生物医学分析杂志, 2007Co-Authors: Liu Peng, Guo Hui, Guo Hongzhu, Sheng Yuxin, Wang Weixing, Xu Man, Feng Suxiu, Cheng Fei, Dean GuoAbstract:A reversed phase high-performance liquid chromatography method was established for the first time to simultaneously qualify the seven major diterpenoids in Pseudolarix kaempferi, namely pseudolaric acid B O-beta-D-glucopyranoside (1), pseudolaric acid C-2 (2), pseudolaric acid C-1 (3), deacetylpseudolaric acid A (4), pseudolaric acid A O-beta-D-glueopyranoside (5), pseudolaric acid B (6) and pseudolaric acid A (7). The optimal conditions of separation and detection were achieved on an Inertsil ODS-3 column with gradient elution of methanol and 0.5% aqueous acetic acid (v/v) at the flow rate of 0.6 ml min(-1) within 40 min and detection wavelength set at 262 run. All calibration curves showed good linear regression (r(2) > 0.9999) within test ranges. This method provided good accuracy with recoveries in the range of 94.3-106.1% and good precision with R.S.D.s of repeatability and intermediate precision less than 0.57% and 4.67%, respectively. The method was successfully applied to qualitative and quantitative determination of 20 P. kaempferi among the 54 samples collected from different areas. The results revealed that the commercial crude drugs were seriously confused and the developed HPLC assay could be used as a suitable qualitative and quantitative determination method for P. kaempferi. (c) 2007 Elsevier B.V. All rights reserved.Chemistry, AnalyticalPharmacology & PharmacySCI(E)PubMed3ARTICLE3,SI730-7364
Weidong Zhang - One of the best experts on this subject based on the ideXlab platform.
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trisecocycloartane triterpene dilactones from the cones of Pseudolarix amabilis
Phytochemistry Letters, 2021Co-Authors: Wenlin Yuan, Weidong Zhang, Zhengrui Huang, Sijia Xiao, Xiuping Shen, Yunheng ShenAbstract:Abstract Two previously undescribed 3(4), 8(9), 9(10)-trisecocycloartane triterpene dilactones with a featured eleven-membered ring, pseudoladilactones A and B (1-2), together with three known ones (4-5), were isolated from the 80 % ethanol extract of the cones of Pseudolarix amabilis. The structures of compounds 1 and 2 were determined on the basis of analysis of 1D- and 2D-NMR spectroscopic data. The absolute configuration of pseudoladilactones A (1) was elucidated by single crystal X-ray diffraction (CuKα). All isolates were tested for cytototoxicity against four human tumor cell lines A549, HCT116, SK-BR-3, and HepG2.
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3 4 secocycloartane triterpenoids from the cones of Pseudolarix amabilis
Natural Products and Bioprospecting, 2021Co-Authors: Sijia Xiao, Yunheng Shen, Wenlin Yuan, Zhengrui Huang, Weidong ZhangAbstract:Four new 3,4-secocycloartane triterpenoids, pseudolactones A-D (1-4), were isolated from the ethanol extract of the cones of Pseudol arixamabilis. Their structures were established by extensive 1D- and 2D-NMR experiments. The cones of P. arixamabilis are enriched in the ring-expanded or cleaved cycloartane triterpenoids. This work provides new insight into cycloartane triterpenoids from the cones of P. arixamabilis.
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inhibition of hl 60 cell growth via cell cycle arrest and apoptosis induction by a cycloartane labdane heterodimer from Pseudolarix amabilis
Organic and Biomolecular Chemistry, 2016Co-Authors: Xinhui Tian, Yunheng Shen, Rongcai Yue, Niao Yang, Jianping Zhang, Liping Chen, Weidong ZhangAbstract:Pseudolaridimer C (), a rarely encountered cycloartane-labdane Diels-Alder adduct was isolated from the cones of Pseudolarix amabilis. The structure and absolute configuration of were established by comprehensive NMR and CD spectral analysis. The WST-8 assay indicated that time and dose dependently inhibited the proliferation of human leukemia cells HL-60 at 1-10 μM. DAPI and Annexin V-FITC/PI double staining method, and DNA ladder experiments all proved that had significant dose-dependent effects on HL-60 cell apoptosis. A further mechanism study indicated that the apoptosis was associated with the cell cycle arrest during the G2/M phase, and the activation of caspase-9, -3, -7, and poly-(ADP-ribose)-polymerase (PARP).
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pseudolarenone an unusual nortriterpenoid lactone with a fused 5 11 5 6 5 ring system featuring an unprecedented bicyclo 8 2 1 tridecane core from Pseudolarix amabilis
Chemical Communications, 2013Co-Authors: Deyun Kong, Yunheng Shen, Rongcai Yue, Zhuzhen Han, Hu Yuan, Qingxin Liu, Lei Shan, Xianwen Yang, Weidong ZhangAbstract:A phytochemical investigation of the cone of Pseudolarix amabilis led to the isolation of pseudolarenone (1), a structurally novel pentacyclic (5/11/5/6/5) nortriterpenoid lactone with an unprecedented carbon skeleton featuring a unique bicyclo[8.2.1]tridecane core. Its structure and absolute configurations were elucidated by spectroscopic analysis and single crystal X-ray diffraction (CuKα).
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pseudolaridimers a and b hetero cycloartane labdane diels alder adducts from the cone of Pseudolarix amabilis
Organic Letters, 2012Co-Authors: Deyun Kong, Yunheng Shen, Rongcai Yue, Hu Yuan, Lei Shan, Xianwen Yang, Runhui Liu, Weidong ZhangAbstract:Pseudolaridimers A (1) and B (2), two unprecedented heterodimers formed via a [4 + 2] Diels - Alder cycloaddition between a cycloartane triterpenoid unit and a labdane diterpenoid unit, were isolated from the cones of Pseudolarix amabilis. Their structures were established by extensive analysis of HRESIMS and NMR spectra. The absolute configuration of 1 was determined by single crystal X-ray diffraction (Cu K-alpha) of its methyl esterified derivative. Pseudolaridimer A (1) showed strong cytotoxicity against HCT116, ZR-75-30, and HL-60 human tumor cell lines, with IC50 values 9.62, 7.84, 8.29 mu g/mL, respectively. Pseudolaridimer B (2) only exhibited potent inhibition against the HL-60 cell line with an IC50 value of 7.50 mu g/mL.
Peng Liu - One of the best experts on this subject based on the ideXlab platform.
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metabolic pathway and metabolites of total diterpene acid isolated from Pseudolarix kaempferi
Acta pharmaceutica Sinica, 2014Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Shifeng Sun, Dean GuoAbstract:The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.
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characterization of diterpenoids in the bark of Pseudolarix kaempferi by hplc esi msn
Acta pharmaceutica Sinica, 2011Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Jian Han, Jie Kang, Baorong Wang, Dean GuoAbstract:Fragmentation behavior of diterpenoids was investigated by ESI/MS n and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry (HPLC-ESI/MS n ). The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C 4-O bond. Furthermore, the eliminations of substituent groups at C-18, C-7 and C-8 can also be observed in the MS n (n = 3−4) spectra. For C-4 acetoxy subsititued diterpenoids, (M+Na−60) + and (M−H−104)
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simultaneous determination of seven major diterpenoids in Pseudolarix kaempferi by high performance liquid chromatography dad method
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Yuxin Sheng, Weixing Wang, Suxiu Feng, Fei Cheng, Dean GuoAbstract:A reversed phase high-performance liquid chromatography method was established for the first time to simultaneously qualify the seven major diterpenoids in Pseudolarix kaempferi, namely pseudolaric acid B O-beta-D-glucopyranoside (1), pseudolaric acid C2 (2), pseudolaric acid C1 (3), deacetylpseudolaric acid A (4), pseudolaric acid A O-beta-D-glucopyranoside (5), pseudolaric acid B (6) and pseudolaric acid A (7). The optimal conditions of separation and detection were achieved on an Inertsil ODS-3 column with gradient elution of methanol and 0.5% aqueous acetic acid (v/v) at the flow rate of 0.6 ml min(-1) within 40 min and detection wavelength set at 262 nm. All calibration curves showed good linear regression (r2>0.9999) within test ranges. This method provided good accuracy with recoveries in the range of 94.3-106.1% and good precision with R.S.D.s of repeatability and intermediate precision less than 0.57% and 4.67%, respectively. The method was successfully applied to qualitative and quantitative determination of 20 P. kaempferi among the 54 samples collected from different areas. The results revealed that the commercial crude drugs were seriously confused and the developed HPLC assay could be used as a suitable qualitative and quantitative determination method for P. kaempferi.
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cytotoxic diterpenoids from the bark of Pseudolarix kaempferi and their structure activity relationships
Journal of Natural Products, 2007Co-Authors: Peng Liu, Hongzhu Guo, Weixing Wang, Jie Zhang, Jian Han, Jianping Zhou, Tong Zhang, Zhenming Liu, Dean GuoAbstract:Four new diterpenoids, 11S-deacetylpseudolaric acid A (2), deacetylpseudolaric acid A O-beta-d-glucopyranoside (3), deacetylpseudolaric acid A 2,3-dihydroxypropyl ester (4), and deacetylpseudolaric acid B 2,3-dihydroxypropyl ester (5), and nine known diterpenoids were isolated from the bark of Pseudolarix kaempferi. Their structures were determined on the basis of chemical and spectroscopic analyses. In addition, their in vitro cytotoxic activities against three human cancer cell lines and their structure-activity relationships were evaluated.
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benzoic acid allopyranosides from the bark of Pseudolarix kaempferi
Phytochemistry, 2006Co-Authors: Peng Liu, Hongzhu Guo, Yin Tian, Qiao Wang, Dean GuoAbstract:Two benzoic acid allopyranosides, pseudolaroside A and pseudolaroside B, along with seven known compounds were isolated from the bark of Pseudolarix kaempferi. Their structures were determined by analysis of HR-ESI-MS, 1D and 2D NMR spectroscopic data, chemical analysis and comparison to the literature data.
Hui Guo - One of the best experts on this subject based on the ideXlab platform.
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oxidatively rearranged cycloartane triterpenoids from the seeds of Pseudolarix amabilis
Natural Product Research, 2018Co-Authors: Hui Guo, Shen Yao, Xinyi Yang, Yunfei Chen, Yan Chen, Feng Gong, Jun Tong, Junqing Qian, Ailian Zhang, Xiaohua CaiAbstract:One novel and eight known oxidatively rearranged cycloartane triterpenoids were isolated from the seeds of Pseudolarix amabilis. The structure of the new isolate was elucidated on extensive spectro...
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Oxidatively rearranged cycloartane triterpenoids from the seeds of Pseudolarix amabilis
2017Co-Authors: Hui Guo, Shen Yao, Xinyi Yang, Yunfei Chen, Yan Chen, Feng Gong, Jun Tong, Junqing Qian, Ailian Zhang, Xiaohua CaiAbstract:One novel and eight known oxidatively rearranged cycloartane triterpenoids were isolated from the seeds of Pseudolarix amabilis. The structure of the new isolate was elucidated on extensive spectroscopic analyses. Results indicated that pseudolarolide Q (4) exhibited strong antimicrobial activity against Gram-positive Staphylococcus aureus and Candida albicans at the MICs of 6.08 and 24.32 μM, respectively. Pseudolarolide I (2) showed the 11β-HSD1 inhibitory property at the IC50 value of 34.5 nM.
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metabolic pathway and metabolites of total diterpene acid isolated from Pseudolarix kaempferi
Acta pharmaceutica Sinica, 2014Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Shifeng Sun, Dean GuoAbstract:The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.
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characterization of diterpenoids in the bark of Pseudolarix kaempferi by hplc esi msn
Acta pharmaceutica Sinica, 2011Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Jian Han, Jie Kang, Baorong Wang, Dean GuoAbstract:Fragmentation behavior of diterpenoids was investigated by ESI/MS n and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry (HPLC-ESI/MS n ). The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C 4-O bond. Furthermore, the eliminations of substituent groups at C-18, C-7 and C-8 can also be observed in the MS n (n = 3−4) spectra. For C-4 acetoxy subsititued diterpenoids, (M+Na−60) + and (M−H−104)
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simultaneous determination of seven major diterpenoids in Pseudolarix kaempferi by high performance liquid chromatography dad method
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Yuxin Sheng, Weixing Wang, Suxiu Feng, Fei Cheng, Dean GuoAbstract:A reversed phase high-performance liquid chromatography method was established for the first time to simultaneously qualify the seven major diterpenoids in Pseudolarix kaempferi, namely pseudolaric acid B O-beta-D-glucopyranoside (1), pseudolaric acid C2 (2), pseudolaric acid C1 (3), deacetylpseudolaric acid A (4), pseudolaric acid A O-beta-D-glucopyranoside (5), pseudolaric acid B (6) and pseudolaric acid A (7). The optimal conditions of separation and detection were achieved on an Inertsil ODS-3 column with gradient elution of methanol and 0.5% aqueous acetic acid (v/v) at the flow rate of 0.6 ml min(-1) within 40 min and detection wavelength set at 262 nm. All calibration curves showed good linear regression (r2>0.9999) within test ranges. This method provided good accuracy with recoveries in the range of 94.3-106.1% and good precision with R.S.D.s of repeatability and intermediate precision less than 0.57% and 4.67%, respectively. The method was successfully applied to qualitative and quantitative determination of 20 P. kaempferi among the 54 samples collected from different areas. The results revealed that the commercial crude drugs were seriously confused and the developed HPLC assay could be used as a suitable qualitative and quantitative determination method for P. kaempferi.
Hongzhu Guo - One of the best experts on this subject based on the ideXlab platform.
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metabolic pathway and metabolites of total diterpene acid isolated from Pseudolarix kaempferi
Acta pharmaceutica Sinica, 2014Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Shifeng Sun, Dean GuoAbstract:The preliminary metabolic profile of total diterpene acid (TDA) isolated from Pseudolarix kaempferi was investigated by using in vivo and in vitro tests. Pseudolaric acid C2 (PC2) was identified as the predominant metabolite in plasma, urine, bile and feces after both oral and intravenous administrations to rats using HPLC-UV and HPLC-ESI/MS(n), and demethoxydeacetoxypseudolaric acid B (DDPB), a metabolite proposed to be the glucoside of PC2 (PC2G), as well as pseudolaric acid C (PC), pseudolaric acid A (PA), pseudolaric acid A O-beta-D glucopyranoside (PAG), pseudolaric acid B O-beta-D glucopyranoside (PBG) and deacetylpseudolaric acid A (DPA) originated from TDA could also be detected. It was demonstrated by tests that the metabolism of TDA is independent of intestinal microflora, and neither of pepsin and trypsin is in charge of metabolism of TDA, TDA is also stable in both pH environments of gastric tract and intestinal tract. The metabolites of TDA in whole blood in vitro incubation were found to be PC2, DDPB and PC2G, which demonstrated that the metabolic reaction of TDA in vivo is mainly occurred in blood and contributed to be the hydrolysis of plasma esterase to ester bond, as well as the glucosylation reaction. These results clarified the metabolic pathway of TDA for the first time, which is of great significance to the in vivo active form and acting mechanism research of P. kaempferi.
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characterization of diterpenoids in the bark of Pseudolarix kaempferi by hplc esi msn
Acta pharmaceutica Sinica, 2011Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Jianghao Sun, Jian Han, Jie Kang, Baorong Wang, Dean GuoAbstract:Fragmentation behavior of diterpenoids was investigated by ESI/MS n and the qualitative analysis of diterpenoids in the bark of Pseudolarix kaempferi was performed using high-performance liquid chromatography/ multi-stage mass spectrometry (HPLC-ESI/MS n ). The characteristic fragmentation behaviors of the diterpenoids are the cleavages of the lactone ring and C 4-O bond. Furthermore, the eliminations of substituent groups at C-18, C-7 and C-8 can also be observed in the MS n (n = 3−4) spectra. For C-4 acetoxy subsititued diterpenoids, (M+Na−60) + and (M−H−104)
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simultaneous determination of seven major diterpenoids in Pseudolarix kaempferi by high performance liquid chromatography dad method
Journal of Pharmaceutical and Biomedical Analysis, 2007Co-Authors: Peng Liu, Hui Guo, Hongzhu Guo, Yuxin Sheng, Weixing Wang, Suxiu Feng, Fei Cheng, Dean GuoAbstract:A reversed phase high-performance liquid chromatography method was established for the first time to simultaneously qualify the seven major diterpenoids in Pseudolarix kaempferi, namely pseudolaric acid B O-beta-D-glucopyranoside (1), pseudolaric acid C2 (2), pseudolaric acid C1 (3), deacetylpseudolaric acid A (4), pseudolaric acid A O-beta-D-glucopyranoside (5), pseudolaric acid B (6) and pseudolaric acid A (7). The optimal conditions of separation and detection were achieved on an Inertsil ODS-3 column with gradient elution of methanol and 0.5% aqueous acetic acid (v/v) at the flow rate of 0.6 ml min(-1) within 40 min and detection wavelength set at 262 nm. All calibration curves showed good linear regression (r2>0.9999) within test ranges. This method provided good accuracy with recoveries in the range of 94.3-106.1% and good precision with R.S.D.s of repeatability and intermediate precision less than 0.57% and 4.67%, respectively. The method was successfully applied to qualitative and quantitative determination of 20 P. kaempferi among the 54 samples collected from different areas. The results revealed that the commercial crude drugs were seriously confused and the developed HPLC assay could be used as a suitable qualitative and quantitative determination method for P. kaempferi.
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cytotoxic diterpenoids from the bark of Pseudolarix kaempferi and their structure activity relationships
Journal of Natural Products, 2007Co-Authors: Peng Liu, Hongzhu Guo, Weixing Wang, Jie Zhang, Jian Han, Jianping Zhou, Tong Zhang, Zhenming Liu, Dean GuoAbstract:Four new diterpenoids, 11S-deacetylpseudolaric acid A (2), deacetylpseudolaric acid A O-beta-d-glucopyranoside (3), deacetylpseudolaric acid A 2,3-dihydroxypropyl ester (4), and deacetylpseudolaric acid B 2,3-dihydroxypropyl ester (5), and nine known diterpenoids were isolated from the bark of Pseudolarix kaempferi. Their structures were determined on the basis of chemical and spectroscopic analyses. In addition, their in vitro cytotoxic activities against three human cancer cell lines and their structure-activity relationships were evaluated.
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benzoic acid allopyranosides from the bark of Pseudolarix kaempferi
Phytochemistry, 2006Co-Authors: Peng Liu, Hongzhu Guo, Yin Tian, Qiao Wang, Dean GuoAbstract:Two benzoic acid allopyranosides, pseudolaroside A and pseudolaroside B, along with seven known compounds were isolated from the bark of Pseudolarix kaempferi. Their structures were determined by analysis of HR-ESI-MS, 1D and 2D NMR spectroscopic data, chemical analysis and comparison to the literature data.
