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Updated: Aug 5, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
Published on: December 26, 2011
Orally bioavailable, indole-based nonpeptide GnRH receptor antagonists with high potency and functional activity
W T Ashton1, R M Sisco, G R Kieczykowski
1Department of Medicinal Chemistry, Merck Research Laboratories, PO Box 2000, NJ 07065-0900, Rahway, USA
Abstract:
Stereospecific introduction of a methyl group to the indole-3-side chain enhanced activity in our tryptamine-derived series of GnRH receptor antagonists. Further improvements were achieved by variation of the bicyclic amino moiety of the tertiary amide and by adjustment of the tether length to a pyridine or pyridone terminus. These modifications culminated in analogue 24, which had oral activity in a rat model and acceptable oral bioavailability and half-life in dogs and monkeys.
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