The Experts below are selected from a list of 24 Experts worldwide ranked by ideXlab platform
Marjaliisa Riekkola - One of the best experts on this subject based on the ideXlab platform.
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A simplified procedure for indole alkaloid extraction from Catharanthus roseus combined with a semi-synthetic production process for vinblastine. Molecules 2007
2013Co-Authors: Arvind Verma, Into Laakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Abstract: Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4’-methylene-bis-3hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semisynthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20 % for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra ofMolecules 2007, 12 1308 vinblastine were dominated by the corresponding protonated molecular ion [M+H] + at m/
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a simplified procedure for indole alkaloid extraction from catharanthus roseus combined with a semi synthetic production process for vinblastine
Molecules, 2007Co-Authors: Arvind Verma, Into Laakso, Tuulikki Seppanenlaakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4'-methylene-bis-3- hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi- synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of
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A Simplified Procedure for Indole Alkaloid Extraction from Catharanthus roseus Combined with a Semi-synthetic Production Process for Vinblastine
MDPI AG, 2007Co-Authors: Marjaliisa Riekkola, Aarre Huhtikangas, Into Laakso, Tuulikki Seppänen-laakso, Arvind VermaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4-methylene-bis-3-hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi-synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen (1O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of vinblastine were dominated by the corresponding protonated molecular ion [M+H]+ at m/z 811 and the characteristic fragment ions matched with those of the standard compound
Arvind Verma - One of the best experts on this subject based on the ideXlab platform.
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A simplified procedure for indole alkaloid extraction from Catharanthus roseus combined with a semi-synthetic production process for vinblastine. Molecules 2007
2013Co-Authors: Arvind Verma, Into Laakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Abstract: Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4’-methylene-bis-3hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semisynthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20 % for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra ofMolecules 2007, 12 1308 vinblastine were dominated by the corresponding protonated molecular ion [M+H] + at m/
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a simplified procedure for indole alkaloid extraction from catharanthus roseus combined with a semi synthetic production process for vinblastine
Molecules, 2007Co-Authors: Arvind Verma, Into Laakso, Tuulikki Seppanenlaakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4'-methylene-bis-3- hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi- synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of
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A Simplified Procedure for Indole Alkaloid Extraction from Catharanthus roseus Combined with a Semi-synthetic Production Process for Vinblastine
MDPI AG, 2007Co-Authors: Marjaliisa Riekkola, Aarre Huhtikangas, Into Laakso, Tuulikki Seppänen-laakso, Arvind VermaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4-methylene-bis-3-hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi-synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen (1O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of vinblastine were dominated by the corresponding protonated molecular ion [M+H]+ at m/z 811 and the characteristic fragment ions matched with those of the standard compound
Jian Zhang - One of the best experts on this subject based on the ideXlab platform.
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Embonic Acid functionalized niobium complexes with selective dye sorption properties
Inorganic Chemistry, 2018Co-Authors: Lvbing Yuan, Lei Zhang, Jian ZhangAbstract:Presented here are binuclear Nb2, tetranuclear Ti2Nb2, and dodecanuclear Nb12 complexes decorated by Embonic Acid ligands. These structures feature a unique Ti-O-Nb or Nb-O-Nb subunit. Besides, the unprecedented dodecanuclear Nb12 cluster further displays a porous three-dimensional packing framework and stability in water, affording an interesting selective uptake for methylene blue molecules over rhodamine B.
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Embonic Acid Functionalized Niobium Complexes with Selective Dye Sorption Properties
2018Co-Authors: Lvbing Yuan, Lei Zhang, Jian ZhangAbstract:Presented here are binuclear Nb2, tetranuclear Ti2Nb2, and dodecanuclear Nb12 complexes decorated by Embonic Acid ligands. These structures feature a unique Ti–O–Nb or Nb–O–Nb subunit. Besides, the unprecedented dodecanuclear Nb12 cluster further displays a porous three-dimensional packing framework and stability in water, affording an interesting selective uptake for methylene blue molecules over rhodamine B
Aarre Huhtikangas - One of the best experts on this subject based on the ideXlab platform.
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A simplified procedure for indole alkaloid extraction from Catharanthus roseus combined with a semi-synthetic production process for vinblastine. Molecules 2007
2013Co-Authors: Arvind Verma, Into Laakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Abstract: Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4’-methylene-bis-3hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semisynthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20 % for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra ofMolecules 2007, 12 1308 vinblastine were dominated by the corresponding protonated molecular ion [M+H] + at m/
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a simplified procedure for indole alkaloid extraction from catharanthus roseus combined with a semi synthetic production process for vinblastine
Molecules, 2007Co-Authors: Arvind Verma, Into Laakso, Tuulikki Seppanenlaakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4'-methylene-bis-3- hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi- synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of
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A Simplified Procedure for Indole Alkaloid Extraction from Catharanthus roseus Combined with a Semi-synthetic Production Process for Vinblastine
MDPI AG, 2007Co-Authors: Marjaliisa Riekkola, Aarre Huhtikangas, Into Laakso, Tuulikki Seppänen-laakso, Arvind VermaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4-methylene-bis-3-hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi-synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen (1O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of vinblastine were dominated by the corresponding protonated molecular ion [M+H]+ at m/z 811 and the characteristic fragment ions matched with those of the standard compound
Into Laakso - One of the best experts on this subject based on the ideXlab platform.
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A simplified procedure for indole alkaloid extraction from Catharanthus roseus combined with a semi-synthetic production process for vinblastine. Molecules 2007
2013Co-Authors: Arvind Verma, Into Laakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Abstract: Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4’-methylene-bis-3hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semisynthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20 % for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra ofMolecules 2007, 12 1308 vinblastine were dominated by the corresponding protonated molecular ion [M+H] + at m/
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a simplified procedure for indole alkaloid extraction from catharanthus roseus combined with a semi synthetic production process for vinblastine
Molecules, 2007Co-Authors: Arvind Verma, Into Laakso, Tuulikki Seppanenlaakso, Aarre Huhtikangas, Marjaliisa RiekkolaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4'-methylene-bis-3- hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi- synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen ( 1 O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of
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A Simplified Procedure for Indole Alkaloid Extraction from Catharanthus roseus Combined with a Semi-synthetic Production Process for Vinblastine
MDPI AG, 2007Co-Authors: Marjaliisa Riekkola, Aarre Huhtikangas, Into Laakso, Tuulikki Seppänen-laakso, Arvind VermaAbstract:Dried leaves of Catharanthus roseus were extracted with aqueous Acidic 0.1 M solution of HCl. Alkaloid-embonate complexes were obtained as precipitates by treating the extract with an alkaline (NaOH) solution of Embonic Acid (4,4-methylene-bis-3-hydroxynaphtalenecarboxylic Acid). The precipitate mainly consisted of catharanthine and vindoline embonates and it was directly used as the starting material for a semi-synthesis of the anti-cancer bisindole alkaloid vinblastine. The coupling reaction involved oxidation of catharanthine in aqueous Acidic medium by singlet oxygen (1O2), continuously produced in situ by the reaction between H2O2 with NaClO. An excess of NaBH4 was used for the reduction step. Analysis of the reaction mixture indicated a maximum yield of 20% for vinblastine at pH 8.3, based on the initial amount of catharanthine concentration. Direct-injection electrospray ionization mass spectrometry in positive ion mode was used for the identification of vinblastine. The mass spectra of vinblastine were dominated by the corresponding protonated molecular ion [M+H]+ at m/z 811 and the characteristic fragment ions matched with those of the standard compound