Patents by Inventor Stig O. E. Lindholm

Stig O. E. Lindholm 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).

  • A process for the preparation of anhydrous, stable, crystalline delta-form of prazosin hydrochloride
    Patent number: 4873330
    Abstract: Anhydrous, stable, crystalline .delta.-form of prazosin hydrochloride, having an infrared spectrum in potassium bromide of FIG. 1 having the following sharp absorption bands at 7.95.mu., 13.3.mu., and a triplet at 9.95.mu. and the x-ray diffractogram of FIG. 2 having sharp bands in 10.5.degree., 12.0.degree., 16.9.degree., and doublets in 24.5.degree. and 26.5.degree.. The .delta.-form of prazosin hydrochloride is prepared by removing the water of crystallization of prazosin hydrochloride hydrate by azeotropic distillation with selected organic solvents having a boiling point in the range of 55.degree.-160.degree. C. The .delta.-form of prazosin hydrochlorie is useful as a hypotensive agent.
    Type: Grant
    Filed: February 8, 1988
    Date of Patent: October 10, 1989
    Assignee: Orion-yhtyma Oy
    Inventor: Stig O. E. Lindholm
  • Anhydrous, stable, crystalline .delta.-form of prazosin hydrochloride
    Patent number: 4739055
    Abstract: Anhydrous, stable, crystalline .delta.-form of prazosin hydrochloride, having an infrared spectrum in potassium bromide of FIG. 1 having the following sharp absorption bands at 7.95.mu., 13.3.mu. and a triplet at 9.95.mu. and the x-ray diffractogram of FIG. 2 having sharp bands in 10.5.degree., 12.0.degree., 16.9.degree. and doublets in 24.5.degree. and 26.5.degree.. The .delta.-form of prazosin hydrochloride is prepared by removing the water of crystallization of prazosin hydrochloride hydrate by azeotropic distillation with selected organic solvents having a boiling point in the range of 55.degree.-160.degree. C. The .delta.-form of prazosin hydrochloride is useful as a hypotensive agent.
    Type: Grant
    Filed: October 15, 1984
    Date of Patent: April 19, 1988
    Assignee: Orion-yhtyma Oy
    Inventor: Stig O. E. Lindholm