2^′, 6^′-Dimethylphenylalanine : A Useful Aromatic Amino Acid Surrogate for Tyr or Phe Residue in Opioid Peptides

Table 5

GPI assay and opioid receptor preference of DYN analogs.

Peptides	IC50 ± SEM (nM)	𝐾e (nM) value of receptor selective antagonist
		nor-BNI (κ)	CTAP (μ)	N,N(Me)2Dmt-Tic-OH (δ)
DYN(l-13)-NH2	3.14 ± 1.13	l.l	99	98
[Dmp^4]DYN(I-13)-NH2 (26)	32.2 ± 9.16	0.63	108	198
[Dmp^1]DYN(l-13)-NH2 (27)	306 ± 68	10	115	>1000
[Dmp^1,4]DYN(l-13)-NH2 (28)	1341 ± 303	809	595	>100