title: Synthesis and biological activity of position 1 analogs of LH-RH.
abstract: (Formyl-sarcosine)1-LH-RH (I), (acetyl-sarcosine)1-LH-RH (II), (2-pyrrolidone-4-carboxylic acid)1-LH-RH (III), (N-methyl-2-pyrrolidone-4-carboxylic acid)1-LH-RH (IV, hydroxyproline1-LH-RH (V) and (cylcopentane-carboxylic acid)1-LH-RH (VI) were synthesized by solid phase methods on a benzhydrylamine resin support. Peptides I-IV were assayed for LH- and FSH-releasing activity over a 4-h period after subcutaneous infection into immature male rats in order to detect any prolongation ofactivity. The peptides were found to have the following integrated LH-releasing activities compared with LH-RH: I, 64%; II, 72%; III, 19%; IV, 58%. None of the peptides were found to be longer acting than LH-RH. Peptides V and VI were far less active, 0.001% and 1.4%, respectively.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001681:Biological Assay; D005640:Follicle Stimulating Hormone / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D051381:Rats; D013997:Time Factors
chemical_list: D000596:Amino Acids; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone