| abstract |
The invention relates to a process for the preparation of peptides of the general formula in the S glutamic acid or a-aminoadipic acid and Y tyrosine or tryptophan or their esters or amides, which is characterized in that tetrapeptides of the formula wherein Z 'stands for a protective group of the benzyl type, condenses with corresponding tyrosine or tryptophan esters or amides and the protective groups are hydrogenated. The invention further relates to tetrapeptides as intermediates in this process. |