title: Antide B, an antagonist of LHRH with cis-3-(4-pyrazinylcarbonylaminocyclohexyl)alanine in position 5.
abstract: Several LHRH antagonists with trans-3-(4-pyrazinylcarbonylaminocyclohexyl)alanine (trans-PzACAla) in the position 5 were synthesized and their antiovulatory activity was compared with the activity of the analogs containing cis-PzACAla in this position. In all cases cis-isomer produced more potent analogs. Introduction of cis-PzACAla in the position 5 of Antide gave Antide B which completely inhibits ovulation at a dose of 0.5µg/rat. Antide B releases negligible histamine (ED50 = 104µg/mL), and has excellent solubility in water. Also, an improved synthesis of cis-PzACAla is reported, involving the hydrogenation of 4-aminophenylalanine on a rhodium catalyst to give the desired cis-isomer with a 53% yield.
authors.affiliation: Institute for Biomedical Research, University of Texas at Austin, 78712, Austin, Texas, USA.
authors.forename: A
authors.initials: A
authors.lastname: Janecka
authors.forename: T
authors.initials: T
authors.lastname: Janecki
authors.forename: C
authors.initials: C
authors.lastname: Bowers
authors.forename: K
authors.initials: K
authors.lastname: Folkers