Synthesis and biological activities of YkFA analogues: effects of position 4 substitutions and altered ring size on in vitro opioid activity.
Substitution in position 4 of the potent opioid peptide YkFA with aliphatic hydrophobic residues resulted in compounds that retained low nanomolar activities at both mu and delta opioid receptors, while ring contraction by incorporation of diaminobutyric acid in position 2 resulted in a more pronounced decrease in potency at both receptors for the psi[CH(2)NH] pseudopeptide as compared to the all amide parent.
Burden
John E
JE
Department of Chemistry, University of Louisville, Louisville, KY 40292, USA.
Davis
Peg
P
Porreca
Frank
F
Spatola
Arno F
AF
D000595:Amino Acid Sequence; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D013058:Mass Spectrometry; D010456:Peptides, Cyclic / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*
D010456:Peptides, Cyclic; C403249:tyrosyl-cyclo(lysyl-phenylalanyl-alanyl)