Tripeptides of n.sup.3 -4-methoxyfumaryl-l-2,3-diaminopropanoic acid

Abstract

The subject of this present invention is tripeptides of N.sup.3 -4-methoxyfumaryl-L-2,3-diaminopropanoic acid of the general formula ##STR1## where R is a hydrogen atom when R.sub.1 is the dipeptide residue containing the residue of alanine, methonine, valine, leucine or norvaline, or R and R.sub.1 have the same meaning and are the residue of monoaminomonocarboxylic aminoacid, such as those of alanine, methionine, valine, leucine, or norvaline, or R is the dipeptide residue containing the residue of alanine, methionine, valine, leucine, norvaline, lysine, ornithine, sarcosine, 2,4-diaminobutanoic acid and 2,3-diaminopropanoic acid, and R.sub.1 is a hydroxide group, and the method of their obtaining. The method of obtaining involves converting N.sup.2 -tetrbutoxycarbonyl, N.sup.3 -4-methoxyfumaroyl-L-2,3-diaminopropanoic acid into an active ester which is used for acylating a dipeptide or N.sup.2 -tetr-butoxycarbonyl, N.sup.3 -4-methoxyfumaryl-L-2,3-diaminopropanoic acid into an active ester which is used for acylating the aminoacid whereafter the protection of the amino group is removed and the latter is acylated with an active ester of the N-protected aminoacid or N.sup.3 -4-methoxyfumaryl-L-2,3-diaminopropanoic acid is acylated with an active ester of the N-protected dipeptide and the protection of the amino group is removed from the obtained N-protected tripeptide in the medium of a non-polar organic solvent or its mixture with water, whereas the final product in the form of a salt is isolated by being crystallized or being converted into a free acid.