title: Synthesis of four diastereomeric enkephalins incorporating cyclopropyl phenylalanine.
abstract: Four diastereomeric D-Ala2, Leu5-enkephalins have been synthesized and their CD spectra and rat brain binding affinities determined. Only the peptides containing Z-cyclopropyl phenylalanine residues showed strong binding affinity. No correlation between CD spectra and bioactivity could be made.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism; D002942:Circular Dichroism; D003521:Cyclopropanes; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D016308:Enkephalin, Leucine-2-Alanine; D004745:Enkephalins / Q000494:pharmacology; D007202:Indicators and Reagents; D008297:Male; D009270:Naloxone / Q000378:metabolism; D010649:Phenylalanine / Q000031:analogs & derivatives*; D011487:Protein Conformation; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D003521:Cyclopropanes; D004745:Enkephalins; D007202:Indicators and Reagents; D011957:Receptors, Opioid; C051120:cyclopropylphenylalanine; D009270:Naloxone; D010649:Phenylalanine; D004743:Enkephalin, Leucine; D016308:Enkephalin, Leucine-2-Alanine