PROCESS FOR THE PREPARATION OF LOWER ALKYL ESTERS OF N-L-.alpha.-ASPARTYL-L-PHENYLALANINE AND OF NEW INTERMEDIATES FOR THE PREPARATION THEREOF
CA 1212940 A · Owner: Eprova Ag · Inventors: Muller, Hans R.; Bollinger, Heinrich
Overview
Its claims, description and drawings are in the Canadian Patents Database.
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The invention relates to a selective process for the preparation of N-L-.alpha.-aspartyl-L-phenylalanine-1-lower alkyl ester which comprises:, A. reacting an L-aspartic acid 4-arylmethyl ester with a i) 1,3-diketone; or, ii) acylacetic ester; in the presence of a base to form the salt of i') L-N-(1-alkyl-2-acyl-vinyl)-aspartic acid 4-arylmethyl ester; or, ii') L-N-(1-alkyl-2 alkoxycarbonyl-vinyl)-aspartic acid 4-arylmethyl ester, and then either: 1) reacting salt (i') or (ii') with an organic or inorganic acid halide having the formula X-A wherein, X represents a halogen and A has the meaning indicated hereinafter, or with an acid anhydride to form I, wherein, R represents an alkyl radical …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted October 21, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 21, 2003.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.