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:
Aug. 25, 2026
Filed:
Dec. 23, 2021
Evonik Operations Gmbh, Essen, DE;
Sascha Braune, Dossenheim, DE;
Geert Van Eester, Antwerp, BE;
Hans-Joachim Hasselbach, Gelnhausen, DE;
Claudia Dyballa, Munich, DE;
Evonik Operations GmbH, Essen, DE;
Abstract
The invention relates in particular to a process for the preparation of DL/LD-methionine diketopiperazine (I) characterized in that a DD/LL-methionylmethionine-containing aqueous solution or suspension, which has a pH of 3 to 7, measured using a pH electrode at 20° C., is reacted at a temperature of 150 to 220° C., preferably at 170 to 210° C., until an aqueous solution or suspension has formed containing at least a proportion of 30 mol %, preferably 50 mol %, especially 60 mol % of DL/LD-methionine diketopiperazine, based on the total content of DL/LD- and DD/LL-methionine diketopiperazine in the reaction mixture. This process forms part of an overall process for the preparation of DL/LD-methionylmethionine, which is obtained by hydrolysis from the DL/LD-methionine diketopiperazine (I) produced initially.