Patents Assigned to Chaichem Pharmaceuticals International
  • Patent number: 6759539
    Abstract: Disclosed is a process for isolating and purifying paclitaxel from a natural resource of taxanes, comprising the steps of (a) washing a raw material comprising paclitaxel with water in order to remove soluble impurities from the raw material; (b) extracting with an organic solvent a wet raw material comprising paclitaxel; (c) contacting the wet raw material with a salt to obtain a biomass by precipitation, isolation, and drying; (d) removing resin and natural pigments from the dried biomass by dissolving the biomass in acetone or an acetone-hexane mixture, and adding at least one polar solvent until a paclitaxel-enriched oil phase is obtained; and (e) chromatography purifying the paclitaxel-enriched oil phase in a volatile solvent to obtain a purified solution, followed by crystallization.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: July 6, 2004
    Assignee: Chaichem Pharmaceuticals International
    Inventors: Trung Bui-Khac, Michel Potier
  • Patent number: 6452024
    Abstract: A process for the extraction and purification of Paclitaxel from a natural source of taxanes, comprising extracting Paclitaxel with an organic solvent from a natural source of taxanes, and treating the raw material with a base or an acid to obtain a biomass by precipitation. The biomass is isolated and dried, and resin and natural pigments are removed. The biomass is then dissolved in acetone and at least one non-polar solvent is added, until a Paclitaxel-enriched oily phase is obtained. The Paclitaxel-enriched oily phase is then treated with a base or an acid to obtain a second biomass, which is recovered by precipitation and dried. A solution of the second biomass in a volatile solvent is chromatographically purified at least once and crystallized.
    Type: Grant
    Filed: May 26, 2000
    Date of Patent: September 17, 2002
    Assignee: Chaichem Pharmaceuticals International
    Inventors: Trung Bui-Khac, Nicolas Dupuis