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:
Feb. 07, 1978
Filed:
Apr. 29, 1976
Ichiro Chibata, Suita, JA;
Shigeki Yamada, Toyonaka, JA;
Masao Yamamoto, Hirakata, JA;
Hisato Sanematsu, Osaka, JA;
Tanabe Seiyaku Co., Ltd., Osaka, JA;
Abstract
Seed crystals of one optically active enantiomer of 6-chlorotryptophan methanesulfonate or 6-chlorotryptophan benzenesulfonate are added to a supersaturated solution of DL-6-chlorotryptophan methanesulfonate or DL-6-chlorotryptophan benzenesulfonate. Crystallization of the optically active enantiomer results. The crystals are recovered. Alternatively, crystals of the optically active enantiomer may be added to a hot solution of DL-6-chlorotryptophan methanesulfonate or DL-6-chlorotryptophan benzenesulfonate to produce a supersaturated solution. The solution is then cooled to crystallize out the optically active enantiomer. Optically active 6-chlorotryptophan is prepared by treating optically active 6-chlorotryptophan methanesulfonate or 6-chlorotryptophan benzenesulfonate with an alkaline agent or an ion exchange resin.