| abstract |
There is provided peptide derivatives of the general formula <IMAGE> wherein R1, R2 and R3 each represent the characterizing group of an alpha -amino acid of the type normally found in proteins; R4 represents a hydroxy or methyl group; n stands for zero, 1, 2 or 3; the configuration at the carbon atoms designated as (a), (b) and (c) is L (when R1 or R2 NOTEQUAL H); and the configuration at the carbon atom designated as (d) is (R) (when R3 NOTEQUAL H) and pharmaceutically acceptable salts thereof. |