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Dilip D Dhavale - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 1 8 8a tri epi swainsonine 1 2 di epi lentiginosine 9a epi homocastanospermine and 9 deoxy 9a epi homocastanospermine from a d glucose derived aziridine carboxylate and study of their glycosidase inhibitory activities
Organic and Biomolecular Chemistry, 2008Co-Authors: K Ajish S Kumar, Vinod D Chaudhari, Dilip D DhavaleAbstract:The utility of a D-glucose-derived aziridine carboxylate was demonstrated for the synthesis of polyhydroxylated Quinolizidine and indolizidine alkaloids. The chemoselective reduction of 1 followed by two-carbon homologation by the Wittig reaction afforded γ,δ-aziridino-α,β-unsaturated ester9, which on regioselective nucleophilic aziridine ring opening either by using water as a nucleophile or hydrogenation afforded δ-lactams 11/16—true synthons for the synthesis of four structurally different iminosugars, namely Quinolizidine alkaloids5b/5c, swainsonine 6b and lentiginosine 7b analogues. Glycosidase inhibitory activities of these iminosugars were investigated.
Chang Kai Zhang - One of the best experts on this subject based on the ideXlab platform.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Chang Kai ZhangAbstract:Abstract Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L9(3)4 including pressure, temperature, flow rate of CO2 and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 °C and a flow rate of CO2 (2 l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform–methanol–2.3 × 10−2 M NaH2PO4 (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Zhao Jie Cui, Chang Kai ZhangAbstract:Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L(9)(3)(4) including pressure, temperature, flow rate of CO(2) and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 degrees C and a flow rate of CO(2) (2l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform-methanol-2.3 x 10(-2)M NaH(2)PO(4) (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
Guo Ying Zhang - One of the best experts on this subject based on the ideXlab platform.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Chang Kai ZhangAbstract:Abstract Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L9(3)4 including pressure, temperature, flow rate of CO2 and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 °C and a flow rate of CO2 (2 l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform–methanol–2.3 × 10−2 M NaH2PO4 (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Zhao Jie Cui, Chang Kai ZhangAbstract:Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L(9)(3)(4) including pressure, temperature, flow rate of CO(2) and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 degrees C and a flow rate of CO(2) (2l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform-methanol-2.3 x 10(-2)M NaH(2)PO(4) (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
K Ajish S Kumar - One of the best experts on this subject based on the ideXlab platform.
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efficient synthesis of 1 8 8a tri epi swainsonine 1 2 di epi lentiginosine 9a epi homocastanospermine and 9 deoxy 9a epi homocastanospermine from a d glucose derived aziridine carboxylate and study of their glycosidase inhibitory activities
Organic and Biomolecular Chemistry, 2008Co-Authors: K Ajish S Kumar, Vinod D Chaudhari, Dilip D DhavaleAbstract:The utility of a D-glucose-derived aziridine carboxylate was demonstrated for the synthesis of polyhydroxylated Quinolizidine and indolizidine alkaloids. The chemoselective reduction of 1 followed by two-carbon homologation by the Wittig reaction afforded γ,δ-aziridino-α,β-unsaturated ester9, which on regioselective nucleophilic aziridine ring opening either by using water as a nucleophile or hydrogenation afforded δ-lactams 11/16—true synthons for the synthesis of four structurally different iminosugars, namely Quinolizidine alkaloids5b/5c, swainsonine 6b and lentiginosine 7b analogues. Glycosidase inhibitory activities of these iminosugars were investigated.
Jianya Ling - One of the best experts on this subject based on the ideXlab platform.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Chang Kai ZhangAbstract:Abstract Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L9(3)4 including pressure, temperature, flow rate of CO2 and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 °C and a flow rate of CO2 (2 l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform–methanol–2.3 × 10−2 M NaH2PO4 (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
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supercritical fluid extraction of Quinolizidine alkaloids from sophora flavescens ait and purification by high speed counter current chromatography
Journal of Chromatography A, 2007Co-Authors: Jianya Ling, Guo Ying Zhang, Zhao Jie Cui, Chang Kai ZhangAbstract:Supercritical fluid extraction (SFE) was used to extract Quinolizidine alkaloids from Sophora flavescens Ait. (Kushen). An orthogonal test L(9)(3)(4) including pressure, temperature, flow rate of CO(2) and the amount of modifier was performed to get the optimal conditions. The process was then scaled up by 30 times with a preparative SFE system under 25 MPa, 50 degrees C and a flow rate of CO(2) (2l/min) and the amount of modifier (0.04 ml/min). The crude extracts were separated and purified by high-speed counter-current chromatography (HSCCC) with a two-phase solvent system composed of chloroform-methanol-2.3 x 10(-2)M NaH(2)PO(4) (27.5:20:12.5, v/v), and the collected fractions were analyzed by high-performance liquid chromatography (HPLC). Three kinds of Quinolizidine alkaloids were obtained, yielding 10.02 mg of matrine, 22.07 mg of oxysophocarpine and 79.93 mg of oxymatrine with purities of 95.6, 95.8, 99.6% in one-step separation, respectively.
