Patents by Inventor Hans D. Lehnen

Hans D. Lehnen 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 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-3-indoleacetoxyacetic acid
    Patent number: 4477677
    Abstract: The invention relates to a process for preparing 1-(4-chlorobenzoyl)-5-methoxy-2-methyl-3-indoleacetoxyacetic acid which comprises reacting an indolecarboxylic acid or its derivatives with a compound of the formula HO--CH.sub.2 --CO--O--R.sup.2 in the presence of an inert organic solvent in a temperature range from -10.degree. C. to 80.degree. C., so that the resulting product is essentially free from the dechlorinated bi-product. The product of the process of the invention is a known anti inflammatory agent.
    Type: Grant
    Filed: February 25, 1983
    Date of Patent: October 16, 1984
    Assignee: Troponwerke GmbH & Co. KG
    Inventors: Karl-Heinz Boltze, Hans D. Lehnen