Patents Examined by Joe Kight
  • Patent number: 5744595
    Abstract: The present invention describes a novel 2'-O-alkylation reaction to produce a novel series of nucleosides carrying the 2'-O-propargyl group, using propargyl bromide, dibutyl tin oxide and tetrabutyl ammonium bromide. The procedure involves novel techniques for regioselective introduction of 2'-/3'-O-propargyl group directly on the 5'-DMT-N-protected- nucleosides using dibutyl tin oxide as a mild base in conjunction with a phase transfer catalyst, tetrabutyl ammonium bromide. The reaction process has many significant features and leads to isomeric ratios in favor of the 2'-regio isomer. This allows the synthesis of the corresponding phosphoramidites of high purity.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: April 28, 1998
    Assignee: ChemGenes Corporation
    Inventors: Suresh C. Srivastava, Syed Kazim Raza