Synthesis and Biological Properties of the 2-l-β-(Pyrazolyl-1)alanine Analogs of Luteinizing Hormone-Releasing Hormone and Thyrotropin-Releasing Hormone

David H. Coy, Yoshihiro Hirotsu, Tommie W. Redding, Esther J. Coy, Andrew V. Schally

Research output: Contribution to journalArticle

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The luteinizing hormone-releasing hormone (LH-RH) analog, <Glu-Pyr(1)Ala-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2, and the thyrotropin-releasing hormone (TRH) analog, <Glu-Pyr(1)Ala-Pro-NH2, were synthesized by azide couplings of the dipeptide hydrazide, <Glu-Pyr(1)Ala-NHNH2, to the C-terminal octapeptide of LH-RH and to proline amide, respectively. In an ovariectomized, steroid-blocked rat assay, the LH-RH analog was found to have only 1% of the LH-releasing activity of the natural hormone. The TRH analog was 1.5 times more effective than TRH itself in releasing TSH in vivo from the anterior pituitary of mice. This peptide is one of two synthetic peptides so far discovered which are more potent than TRH.

Original languageEnglish (US)
Pages (from-to)948-949
Number of pages2
JournalJournal of Medicinal Chemistry
Issue number9
StatePublished - Sep 1 1975


ASJC Scopus subject areas

  • Molecular Medicine
  • Drug Discovery

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