Patents by Inventor Lijun Mei

Lijun Mei 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).

  • Process for the preparation of cladribine
    Patent number: 8232387
    Abstract: A process for the preparation of cladribine of API grade is provided by direct coupling of O-protected 2-deoxy-ribofuranose with silylated 2-chloroadenine followed by deprotection of the resultant protected nucleoside in a separate step and then a purification step. Following the coupling, the desired N-9-glycosylated ?-anomer of the nucleoside is directly isolated as a solid from the coupling reaction mixture by filtration in relatively high purity and yield, and it does not require purification.
    Type: Grant
    Filed: August 17, 2010
    Date of Patent: July 31, 2012
    Assignee: ScinoPharm Taiwan, Ltd.
    Inventors: Julian Paul Henschke, Xiaoheng Zhang, Guodong Chu, Lijun Mei, Yung Fa Chen
  • Preparation of 2-chloro-9-(2'-deoxy-2'-fluoro-Beta-D-arabinofuranosyl)-adenine
    Publication number: 20120010397
    Abstract: A process for making clofarabine comprising: fluorinating a compound of formula VII wherein each R4 is independently a hydroxy protecting group, OR6 is a leaving group, with a fluorinating agent in the presence of guanidine carbonate to give a compound of formula VIII: wherein R4 is as defined above; and deprotecting the compound of formula VIII to give the clofarabine.
    Type: Application
    Filed: July 8, 2011
    Publication date: January 12, 2012
    Inventors: Julian Paul Henschke, Xiaoheng Zhang, Lijun Mei, Yung-Fa Chen
  • Process for the Preparation of Cladribine
    Publication number: 20110046363
    Abstract: A process for the preparation of cladribine of API grade is provided by direct coupling of O-protected 2-deoxy-ribofuranose with silylated 2-chloroadenine followed by deprotection of the resultant protected nucleoside in a separate step and then a purification step. Following the coupling, the desired N-9-glycosylated ?-anomer of the nucleoside is directly isolated as a solid from the coupling reaction mixture by filtration in relatively high purity and yield, and it does not require purification.
    Type: Application
    Filed: August 17, 2010
    Publication date: February 24, 2011
    Inventors: Julian Paul Henschke, Xiaoheng Zhang, Guodong Chu, Lijun Mei, Yung Fa Chen
  • Synthesis of Decitabine
    Publication number: 20100087637
    Abstract: A method for producing a ?-enriched protected decitabine comprising: a) coupling a protected 2-deoxy-ribofuranose with a protected 5-azacytosine in the presence of a catalyst to form a reaction mixture comprising the protected decitabine of formula I; and b) quenching the reaction mixture of step a) with a base. The ?-enriched protected decitabine so made may be deprotected to produce a decitabine product in a high yield and purity.
    Type: Application
    Filed: October 2, 2009
    Publication date: April 8, 2010
    Inventors: Julian Paul Henschke, Xiaoheng Zhang, Jianbo Yu, Kun Hu, Lijun Mei