Patents by Inventor Yong Y. Chen

Yong Y. Chen has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • One pot synthesis of tetrazole derivatives of rapamycin
    Patent number: 8129521
    Abstract: A single-step, one-pot process to obtain zotarolimus and other rapamycin derivatives on large scale is presented, which improves currently available synthesis schemes. In one embodiment, dried rapamycin is dissolved in isopropylacetate (IPAc). The solution is cooled, and 2,6-Lutidine is added, followed slowly adding triflic anhydride at ?30° C. Salts are then removed by filtration. Tetrazole, followed by a tert-base diisopropylethylamine (DIEA) is added to the triflate solution. After incubation at room temperature, the product is concentrated and purified by a silica gel column using THF/heptane as eluant. The fractions containing the product are collected, concentrated, and purified again using an acetone/heptane column. The product containing fractions are concentrated. The product is dissolved in t-BME and precipitated with heptane. The solids are dissolved in acetone, treated with butylated-hydroxy toluene (BHT), and the solution concentrated.
    Type: Grant
    Filed: February 23, 2010
    Date of Patent: March 6, 2012
    Assignee: Abbott Laboratories
    Inventors: Madhup K. Dhaon, Chi-nung Hsiao, Subhash R. Patel, Peter J. Bonk, Sanjay R. Chemburkar, Yong Y. Chen
  • One pot synthesis of tetrazole derivatives of sirolimus
    Publication number: 20080167335
    Abstract: A single-step, one-pot process to obtain zotarolimus and other rapamycin derivatives on large scale is presented, which improves currently available synthesis schemes. In one embodiment, dried rapamycin is dissolved in isopropylacetate (IPAc). The solution is cooled, and 2,6-Lutidine is added, followed slowly adding triflic anhydride at ?30° C. Salts are then removed by filtration. Tetrazole, followed by a tert-base diisopropylethylamine (DIEA) is added to the triflate solution. After incubation at room temperature, the product is concentrated and purified by a silica gel column using THF/heptane as eluant. The fractions containing the product are collected, concentrated, and purified again using an acetone/heptane column. The product containing fractions are concentrated. The product is dissolved in t-BME and precipitated with heptane. The solids are dissolved in acetone, treated with butylated-hydroxy toluene (BHT), and the solution concentrated.
    Type: Application
    Filed: December 14, 2005
    Publication date: July 10, 2008
    Inventors: Madhup K. Dhaon, Chi-nung Hsiao, Subhash R. Patel, Peter J. Bonk, Sanjay R. Chemburkar, Yong Y. Chen