Patents by Inventor Walter A. M. Helsen

Walter A. M. Helsen 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).

  • Racemates and optical isomers of 1-(1-phenylethyl)-1H-imidazole-5-carboylic acid derivatives
    Patent number: 4038286
    Abstract: Novel methods of preparing lower alkyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylates in racemic as well as in optically pure isomeric form.
    Type: Grant
    Filed: September 12, 1975
    Date of Patent: July 26, 1977
    Assignee: Janssen Pharmaceutica N.V.
    Inventors: Leopold Fr. C. Roevens, Jozef J. P. Heykants, Walter A. M. Helsen
  • Racemization of lower alkyl imidazole carboxylates
    Patent number: 3991072
    Abstract: Novel methods of preparing lower alkyl 1-(1-phenylethyl)-1H-imidazole-5-carboxylates in racemic as well as in optically pure isomeric form.
    Type: Grant
    Filed: September 12, 1975
    Date of Patent: November 9, 1976
    Assignee: Janssen Pharmaceutica N.V.
    Inventors: Leopold Fr. C. Roevens, Jozef J. P. Heykants, Walter A. M. Helsen