Preparation process of .alpha.-l-aspartyl-l-phenyl-alanine methyl ester or hydrohalide thereof
US4918216A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 1989 |
| Grant date | Apr 17, 1990 |
| Priority date | — |
| Expiry date | May 25, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07K5/0613
- WIPO fieldBiotechnology
- WIPO sectorChemistry
Abstract
.alpha.-L-aspartyl-L-phenylalanine methyl ester or the hydrohalide thereof is prepared by esterifying .alpha.-L-aspartyl-L-phenylalanine or .alpha.-L-aspartyl-L-phenylalanine which has been formed in situ by treating an N-protected-.alpha.-L-aspartyl-L-phenylalanine in an aqueous solution of sulfuric acid or a methanol-containing aqueous solution of sulfuric acid in the presence of an alkali metal halide or alkaline earth metal halide in a medium composed of sulfuric acid, water and methanol, thereby to allow the resulting .alpha.-L-aspartyl-L-phenyl-alanine methyl ester to precipitate as its corresponding hydrohalide, and then isolating the hydrohalide; and when the preparation of the methyl ester is desired, neutralizing the hydrohalide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.