Synthesis of erythro- and threo-γ-Hydroxy-L-ornithines

• Published in: Bulletin of the Chemical Society of Japan Vol. 53; no. 9; pp. 2605 - 2609
• Main Authors: Mizusaki, Koichi, Yamamoto, Hidefumi, Makisumi, Satoru
• Format: Journal Article
• Language: English
• Published: The Chemical Society of Japan 01.09.1980
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.53.2605

γ-Hydroxy-DL-ornithine was obtained from an alkaline hydrolysate of 2,5-diamino-4-pentanolide synthesized according to the method of Talbot et al. The amino acid preparation was found to be a racemic mixture composed of 34% erythro and 66% threo isomers by a new chromatographic assay. This assay is based on the conversion of the basic amino acid to a neutral amino acid by acetylation of the δ-amino group and the analysis of the resulting Nδ-acetyl derivative with an automatic amino acid analyzer by the ordinary method. Two diastereoisomers of γ-hydroxy-DL-ornithine were separated by column chromatography on Dowex 50 and isolated as their crystalline hydrochlorides. Guanidination of the separated racemic diastereoisomers gave the corresponding diastereoisomeric γ-hydroxyarginines, hydrolysis of which with arginase yielded erythro- and threo-γ-hydroxy-DL-ornithines.