Patents Represented by Attorney Donald L. Johson

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  • Preparation of 1-alkyl-1,4-dihydro-4-oxo-7-(4-pyridyl)-3-quinoline carboxylic acid
    Patent number: 4550167
    Abstract: Diels-Alder products obtained by reacting a haloprene with a 4-vinylpyridine, i.e., mixtures of 4-(halocyclohex-3-enyl)pyridine isomers, are reacted with a relatively strong acid, i.e., an acid having a dissociation constant of at least 1.7.times.10.sup.-5 at 25.degree. C., to form salts which are readily separated and/or reduced.
    Type: Grant
    Filed: May 23, 1983
    Date of Patent: October 29, 1985
    Assignee: Ethyl Corporation
    Inventor: Venkataraman Ramachandran