Process for the separation of the racemate (R,S)-cysteine

US4430509A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Horst Bethge · Hanau, DE
• Karlheinz Drauz · Alzenau, DE
• Axel Kleemann · Hanau, DE
• Jurgen Martens · Alzenau, DE
• Horst Weigel · Rodenbach, DE

Key dates

• Filing date: Jan 25, 1983
• Grant date: Feb 7, 1984
• Expiry date: Jan 25, 2003

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07H15/14
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

To separate the racemate (R,S)-cysteine, the racemate is condensed in an inert solvent with an enantiomerically enantiomeric monosaccharide of the group of aldoses having 4 to 7 carbon atoms to form the corresponding 2-substituted thiazolidin-4-carboxylic acid and the mixture of diastereomers obtained separated from each other. Subsequently, the isolated unitary diastereomers are reacted in an inert solvent with a carbonyl reagent to split the ring and the enantiomerically pure cysteine in each case is isolated as such or as the corresponding cystine.