The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 1989
Filed:
Sep. 12, 1985
Satomi Takahashi, Kobe, JP;
Yukio Yamada, Kakogawa, JP;
Yasuyoshi Ueda, Takasago, JP;
Yasuhiro Katayama, Takasago, JP;
Yoshio Shimada, Kakogawa, JP;
Kiyoshi Watanabe, Akashi, JP;
Kanegafuchi Kagaku Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A process for preparing optically active hydantoins having the general formula (II): ##STR1## wherein R.sup.1 and R.sup.2, which are different from each other, are independently alkyl group, aralkyl group, aryl group, substituted alkyl group, substituted aralkyl group, or substituted aryl group, or R.sup.1 and R.sup.2 form an asymmetric cyclic compound, characterized in that one configuration of racemic N-carbamoyl-.alpha.-amino acid having the general formula (I): ##STR2## wherein R.sup.1 and R.sup.2 are as above, is enzymatically converted into the corresponding hydantoins. The present invention provides a process for an optical resolution with a high efficiency which can be used for the synthesis of (S)-6-fluoro-spiro-[chroman-4,4'-imidazolidine]-2',5'-dione (USAN; Sorbinil), which is an optically active hydrantoins attracting public attention as a preventive or a remedy for the particular chronic symptoms of diabetes such as cataract and neuropathy, and (S)-.alpha.-methyl-3,4-dihydroxyphenylalanine (L-methyldopa), which is an optically active amino acid widely used as antihypertensives. Further, the present invention provides a novel finding that N-carbamoyl-.alpha.-amino acid having no hydrogen atom on its .alpha.-carbon atom can be biochemically converted into hydantoins by an enzymatic cyclization reaction.