Patents by Inventor Johannes A. M. Hamersma

Johannes A. M. Hamersma 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).

  • 17-spirofuran-3'-ylidene steroids
    Patent number: 5292878
    Abstract: The invention relates to an antiprogestin 17- spirofuran-3'-ylidene steroid having the formula ##STR1## p0 R.sub.1 is NR.sub.2 R.sub.3, lower acyl, OH, SH, O-lower alkyl or S(O).sub.n -lower alkyl wherein n is 0-2;R.sub.2 and R.sub.3 are independently selected from hydrogen and lower alkyl;R.sub.4 is hydrogen or lower alkyl;R.sub.5 is O, (H,H), (H,OH), (H,O-lower acyl), or NOH;R.sub.6 and R.sub.7 are both hydrogen, or one is hydrogen and the other lower alkyl; andthe twitched line represents an .alpha. or .beta. bond.
    Type: Grant
    Filed: December 21, 1992
    Date of Patent: March 8, 1994
    Assignee: Akzo N.V.
    Inventors: Johannes A. M. Hamersma, Everardus O. M. Orlemans