Effect of Simple Amino Acid Replacements on the Biological Activity of Luteinizing Hormone-Releasing Hormone

David H. Coy, Esther J. Coy, Andrew V. Schally

Research output: Contribution to journalArticle

25 Scopus citations


Six decapeptides having structures based on the LH-RH sequence, <Glu-His-Trp-Ser-Tyr-Gly-Leu-Arg- Pro-Gly-NH2, have been synthesized by modifications of the solid-phase technique via protected peptide intermediates. Thus, pyroglutamic acid, tryptophan, serine, glycine, proline, and glycine amide residues in the LH-RH sequence were replaced by leucine, tyrosine, threonine, isoleucine, alanine, and glycine dimethylamide, respectively. The compounds were assayed in vivo and found to possess the following LH-releasing potencies relative to pure, natural LH-RH: [Leu1]-LH-RH, 0.003%; [Tyr3]-LH-RH, 0.13%; [Thr4]-LH-RH, 19%; [Ile6]-LH-RH, 0.034%; [Ala9]-LH-RH, 0.8%; and [(Gly-dimethylamide)10]-LH-RH, 14%.

Original languageEnglish (US)
Pages (from-to)1140-1143
Number of pages4
JournalJournal of Medicinal Chemistry
Issue number10
StatePublished - Oct 1 1973


ASJC Scopus subject areas

  • Molecular Medicine
  • Drug Discovery

Cite this