Preparation of Optically Active Allothreonine via Optical Resolution by Replacing Crystallization

Autor:	Motoki Kubo, Keiji Fukuda, Tadashi Shiraiwa
Rok vydání:	2002
Předmět:	Threonine Aqueous solution Recrystallization (geology) Stereoisomerism General Chemistry General Medicine Catalysis law.invention chemistry.chemical_compound Salicylaldehyde chemistry law Reagent Yield (chemistry) Drug Discovery Polymer chemistry Organic chemistry Enantiomer Crystallization
Zdroj:	Chemical and Pharmaceutical Bulletin. 50:287-291
ISSN:	1347-5223 0009-2363
Popis:	An attempt was made to use a simple procedure to obtain D- and L-allothreonine (D- and L-aThr), which are non-proteinogenic alpha-amino acids and are useful as chiral reagents in asymmetric syntheses. DL-aThr that exists as a conglomerate was optically resolved by replacing crystallization with L-alanine (L-Ala) as an optically active co-solute. D-aThr was preferentially crystallized from an aqueous solution of DL-aThr in the presence of L.-Ala, as was L-aThr in the presence of D-Ala. Furthermore, a diasteroisomeric mixture of D-aThr and L-threonine (L-Thr) and one of L-aThr and D-Thr were prepared, respectively, by epimerization of L- and D-Thr using salicylaldehyde as the catalyst in acetic acid. Based on the result of the replacing crystallization, D- and L-aThr were separated from aqueous solutions of the diastereoisomeric mixtures in the presence of L- and D-Ala. The partially resolved D- and L-aThr were recrystallized from water to yield the corresponding enantiomers in optically pure forms.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::615b00401f6cef5671ff2b2aa8a4863d https://doi.org/10.1248/cpb.50.287 Zobrazit plný text záznamu