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Medice Chem.-pharm. Fabrik Putter Gmbh & Co. Kg

Gottfried Blaschke

Klaus Huthmacher

Horst Bethge

Thomas Beisswenger

Joachim Kinkel

Roland Moller

Werner Broker

Werner Fraenkel

Karl-Ernst Schulte

Ursula Scheidemantel

The pure enantiomers of alpha-lipoic acid are obtained by formation of the diastereomeric salt pairs with the optical antipodes of alpha-methylbenzylamine in solution.

Preparation and use of salts of the pure enantiomers of alpha-lipoic acid

A process for obtaining enantiomers of 2-arylpropionic acids by reacting a racemic mixture thereof with an amine-enantiomer, which process comprises converting the racemate of the 2-arylpropionic acid with an optically active form of threo-1-p-nitrophenyl-2-aminopropane-1,3-diol into the diastereomeric salts, separating these salts and converting the thus-obtained pure diastereomers into the free acids of the enantiomer forms of the 2-arylpropionic acid or into the salts thereof.

Process for obtaining enantiomers of 2-arylpropionic acids

Absorbents based on optically active poly(meth)acrylamides, e.g. bonded to silica gel, can be used for separating racemic mixtures into their optical antipodes.

Optically active adsorbents

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Munster, Germany

Gottfried Blaschke