Biological active analogues of the opioid peptide biphalin: Mixed α/β3-peptides

摘要

Natural residues of the dimeric opioid peptide Biphalin were replaced by the corresponding homo-β~3 amino acids. The derivative 1 containing hβ~3 Phe in place of Phe showed good μ- and δ-receptor affinities (K_i ~δ = 0.72 nM; K _i ~μ = 1.1 nM) and antinociceptive activity in vivo together with an increased enzymatic stability in human plasma.