Patents by Inventor Dana Chreng

Dana Chreng 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).

  • Patent number: 10618931
    Abstract: Provided herein are methods for the synthesis of oligomeric compounds wherein removal of the 5?-terminal trityl group is performed at reduced temperature and lower pH relative to standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds with increased purity relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide an increased rate of detritylation compared to standard methods.
    Type: Grant
    Filed: July 27, 2017
    Date of Patent: April 14, 2020
    Assignee: Ionis Pharmaceuticals, Inc.
    Inventor: Dana Chreng
  • Patent number: 10450342
    Abstract: Provided herein are methods for removal of monomethoxytrityl groups from oligomeric compounds comprising terminally linked monomethoxytrityl protected amino groups. The present methods differ from standard methods for 5?-dimethoxytrityl removal from oligonucleotides in that the present methods are performed at elevated temperatures and higher pH. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide an increased rate of detritylation compared to standard methods. In certain embodiments, the modification of the final detritylation step results in an improved yield.
    Type: Grant
    Filed: February 23, 2016
    Date of Patent: October 22, 2019
    Assignee: Ionis Pharmaceuticals, Inc.
    Inventors: Dana Chreng, Michael T. Migawa
  • Publication number: 20180044370
    Abstract: Provided herein are methods for removal of monomethoxytrityl groups from oligomeric compounds comprising terminally linked monomethoxytrityl protected amino groups. The present methods differ from standard methods for 5?-dimethoxytrityl removal from oligonucleotides in that the present methods are performed at elevated temperatures and higher pH. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide an increased rate of detritylation compared to standard methods. In certain embodiments, the modification of the final detritylation step results in an improved yield.
    Type: Application
    Filed: February 23, 2016
    Publication date: February 15, 2018
    Applicant: Ionis Pharmaceuticals, Inc.
    Inventors: Dana Chreng, Michael T. Migawa
  • Publication number: 20170327527
    Abstract: Provided herein are methods for the synthesis of oligomeric compounds wherein removal of the 5?-terminal trityl group is performed at reduced temperature and lower pH relative to standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds with increased purity relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide an increased rate of detritylation compared to standard methods.
    Type: Application
    Filed: July 27, 2017
    Publication date: November 16, 2017
    Applicant: Ionis Pharmaceuticals, Inc.
    Inventor: Dana Chreng
  • Patent number: 9758546
    Abstract: Provided herein are methods for the synthesis of oligomeric compounds wherein removal of the 5?-terminal trityl group is performed at reduced temperature and lower pH relative to standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds with increased purity relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present method provide an increased rate of detritylation compared to standard methods.
    Type: Grant
    Filed: October 21, 2014
    Date of Patent: September 12, 2017
    Assignee: Ionis Pharmaceuticals, Inc.
    Inventor: Dana Chreng
  • Publication number: 20160244477
    Abstract: Provided herein are methods for the synthesis of oligomeric compounds wherein removal of the 5?-terminal trityl group is performed at reduced temperature and lower pH relative to standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds having a reduced percentage of depurination relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present methods provide detritylated oligomeric compounds with increased purity relative to the same detritylated oligomeric compounds prepared using standard methods. In certain embodiments, the present method provide an increased rate of detritylation compared to standard methods.
    Type: Application
    Filed: October 21, 2014
    Publication date: August 25, 2016
    Applicant: Ionis Pharmaceuticals, Inc.
    Inventor: Dana Chreng