title: Synthesis of Optically Active 1,4-Thiazane-3-carboxylic Acid via Optical Resolution by Preferential Crystallization of (RS)-2-Amino-3-[(2-chloroethyl)sulfanyl]propanoic Acid Hydrochloride.
abstract: Optically active 1,4-thiazane-3-carboxylic acid [TCA] was synthesized from cysteine via optical resolution by preferential crystallization. The intermediate (RS)-2-amino-3-[(2-chloroethyl)sulfanyl]propanoic acid hydrochlo-ride [(RS)-ACS•HCl] was found to exist as a conglomerate based on its melting point, solubility and IR spectrum. (RS)-ACS•HCl was optically resolved by preferential crystallization to yield (R)- and (S)-ACS•HCl. (R)- and (S)-ACS•HCl thus obtained were recrystallized from a mixture of hydrochloric acid and 2-propanol, taking account of the solubility of (RS)-ACS•HCl, efficiently yielding both enantiomers in optically pure forms. (R)- and (S)-TCA were then respectively synthesized by the cyclization of (R)- and (S)-ACS•HCl in ethanol in the presence of triethylamine.
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: T
authors.initials: T
authors.lastname: Shiraiwa
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: K
authors.initials: K
authors.lastname: Tadokoro
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: H
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: K
authors.initials: K
authors.lastname: Nanba
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: N
authors.initials: N
authors.lastname: Yokono
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: K
authors.initials: K
authors.lastname: Shibazaki
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: M
authors.initials: M
authors.lastname: Kubo
authors.affiliation: a Chemical Branch, Faculty of Engineering and Kansai University High Technology Research Center, Kansai University.
authors.forename: H
authors.initials: H
authors.lastname: Kurokawa
keywords: 1,4-thiazane-3-carboxylic acid; 2-amino-3-[(2-chloroethyl)sulfanyl]propanoic acid hydrochloride; conglomerate; optical resolution; preferential crystallization