Patents by Inventor Kan-Nian Hu

Kan-Nian Hu 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).

  • Publication number: 20140235703
    Abstract: Polymorph Forms M, H, P, X, and ZA of Compound (1) represented by the following structural formula: are described. A method of preparing polymorph Form M of Compound (1) includes stirring a mixture of Compound (1) and a solvent system that includes isopropanol, ethyl acetate, n-butyl acetate, methyl acetate, acetone, 2-butanone (methylethylketone (MEK)), or heptane, or a combination thereof at a temperature in a range of 10° C. to 47° C. to form From M of Compound (1). A method of preparing polymorph Form H of Compound (1) includes stirring a solution of Compound (1) at a temperature in a range of 48° C. to 70° C. to form Form H of Compound (1). A method of preparing polymorph Form P of Compound (1) includes stirring a mixture of Compound (1) and a solvent system that includes a solvent selected from the group consisting of dichloromethane and tetrahydrofuran (THF), and a mixture thereof at room temperature to form Form P of Compound (1).
    Type: Application
    Filed: January 24, 2014
    Publication date: August 21, 2014
    Applicant: Vertex Pharmaceuticals Incorporated
    Inventors: Brian Luisi, David Willcox, Stefanie Roeper, Kan-Nian Hu, Hoa Q. Luong
  • Patent number: 7985594
    Abstract: The present invention provides methods for performing dynamic nuclear polarization using biradicals with a structure of formula (I) as described herein. In general, the methods involve (a) providing a frozen sample in a magnetic field, wherein the frozen sample includes a biradical of formula (I) and an analyte with at least one spin half nucleus; (b) polarizing the at least one spin half nucleus of the analyte by irradiating the frozen sample with radiation having a frequency that excites electron spin transitions in the biradical; (c) optionally melting the sample to produce a molten sample; and (d) detecting nuclear spin transitions in the at least one spin half nucleus of the analyte in the frozen or molten sample. The present invention also provides biradicals with a structure of formula (I) with the proviso that Q1 and Q2 are different when X1 and X2 are —O—. The present invention also provides methods for making biradicals with a structure of formula (IA) as described herein.
    Type: Grant
    Filed: May 10, 2007
    Date of Patent: July 26, 2011
    Assignee: Massachusetts Institute of Technology
    Inventors: Robert G. Griffin, Kan-Nian Hu, Timothy M. Swager, Changsik Song, Eric Dane
  • Publication number: 20090311189
    Abstract: In one aspect, the present invention provides a method for enhancing the sensitivity of liquid-state NMR or MRI experiments. In general, the method involves providing a frozen sample in a magnetic field, wherein the frozen sample includes a polarizing agent with at least one unpaired electron and an analyte with at least one spin half nucleus; polarizing the at least one spin half nucleus of the analyte by irradiating the frozen sample with radiation having a frequency that excites electron spin transitions in the at least one unpaired electron of the polarizing agent; melting the frozen sample to produce a molten sample; and (d) detecting nuclear spin transitions in the at least one spin half nucleus of the analyte in the molten sample. In certain embodiments, the methods further comprise a step of freezing a sample in a magnetic field to provide the frozen sample in a magnetic field.
    Type: Application
    Filed: May 10, 2007
    Publication date: December 17, 2009
    Applicant: Massachusetts Institute of Technology
    Inventors: Robert G. Griffin, Kan-Nian Hu, Chan Gyu Joo
  • Publication number: 20090302842
    Abstract: The present invention provides methods for performing dynamic nuclear polarization using biradicals with a structure of formula (I) as described herein. In general, the methods involve (a) providing a frozen sample in a magnetic field, wherein the frozen sample includes a biradical of formula (I) and an analyte with at least one spin half nucleus; (b) polarizing the at least one spin half nucleus of the analyte by irradiating the frozen sample with radiation having a frequency that excites electron spin transitions in the biradical; (c) optionally melting the sample to produce a molten sample; and (d) detecting nuclear spin transitions in the at least one spin half nucleus of the analyte in the frozen or molten sample. The present invention also provides biradicals with a structure of formula (I) with the proviso that Q1 and Q2 are different when X1 and X2 are —O—. The present invention also provides methods for making biradicals with a structure of formula (IA) as described herein.
    Type: Application
    Filed: May 10, 2007
    Publication date: December 10, 2009
    Applicant: Massachusetts Institute of Tecnology
    Inventors: Robert G. Griffin, Kan-Nian Hu, Timothy M. Swager, Changsik Song, Eric Dane
  • Patent number: 7351402
    Abstract: We describe polarizing agents for use in enhancing NMR and MRI signals via dynamic nuclear polarization (DNP). The polarizing agents include two or more paramagnetic centers, preferably two paramagnetic centers. In a preferred embodiment, the polarizing agent comprises two nitroxide radicals tethered by a polyethylene glycol chain of variable length. Signal enhancements of up to 175 have been achieved in comparison with factors of ˜45 at similar concentrations of monomeric radical such as TEMPO.
    Type: Grant
    Filed: August 18, 2004
    Date of Patent: April 1, 2008
    Assignee: Massachusetts Institute of Technology
    Inventors: Robert G. Griffin, Kan-Nian Hu
  • Publication number: 20050107696
    Abstract: We describe polarizing agents for use in enhancing NMR and MRI signals via dynamic nuclear polarization (DNP). The polarizing agents include two or more paramagnetic centers, preferably two paramagnetic centers. In a preferred embodiment, the polarizing agent comprises two nitroxide radicals tethered by a polyethylene glycol chain of variable length. Signal enhancements of up to 175 have been achieved in comparison with factors of ˜45 at similar concentrations of monomeric radical such as TEMPO.
    Type: Application
    Filed: August 18, 2004
    Publication date: May 19, 2005
    Inventors: Robert Griffin, Kan-Nian Hu