Patents by Inventor Britt I. Keding

Britt I. Keding 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 S-metoprolol via oxazolidin-2-one
    Patent number: 5034535
    Abstract: A process for preparing S-metoprolol of the formula ##STR1## or a salt thereof, with high enantiomeric purity, is described, whereby a (S)-5-hydroxymethyl-3-isopropyloxazolidin-2-one sulfonic acid ester of the formula ##STR2## is prepared, and further reacted with 4-[2-methoxyethyl]phenol of the formula ##STR3## and the resulting intermediate of the formula ##STR4## is hydrolysed to S-metoprolol, and whereby the (S)-5-hydroxymethyl-3-isopropyloxazolidin-2-one sulfonic acid ester of formula II is prepared by reacting (S)-3-isopropylamino-1,2-propanediol of the formula ##STR5## with a chloroformic acid ester of the formula ##STR6## wherein R' is an alkyl group having 1-3 carbon atoms or a phenyl group, to the formation of (S)-5-hydroxymethyl-3-isopropyloxazolidin-2-one of the formula ##STR7## which is reacted with an activated sulfonic acid of the formula ##STR8## wherein R" is an aryl group such as tolyl and X is a halogen such as Cl, to formation of the ester of formula II, which when required is enriched wit
    Type: Grant
    Filed: May 30, 1990
    Date of Patent: July 23, 1991
    Assignee: Astra Pharmaceutical Production Aktiebolag
    Inventors: Britt I. Keding, Bo A. R. Lindqvist, Bengt B. Samuelsson