Document Report Card

ID: ALA1131032

Journal: J Med Chem

Title: Selective endothelin A receptor antagonists. 3. Discovery and structure-activity relationships of a series of 4-phenoxybutanoic acid derivatives.

Authors: Astles PC, Brealey C, Brown TJ, Facchini V, Handscombe C, Harris NV, McCarthy C, McLay IM, Porter B, Roach AG, Sargent C, Smith C, Walsh RJ.

Abstract: The third in this series of papers describes our further progress into the discovery of a potent and selective endothelin A (ETA) receptor antagonist for the potential treatment of diseases in which a pathophysiological role for endothelin has been implicated. These include hypertension, ischemic diseases, and atherosclerosis. In earlier publications we have outlined the discovery and structure-activity relations of two moderately potent series of nonpeptide ETA receptor antagonists. In this paper, we describe how a pharmacophore model for ETA receptor binding was developed which enabled these two series of compounds to be merged into a single class of 4-phenoxybutanoic acid derivatives. The subsequent optimization of in vitro activity against the ETA receptor led to the discovery of (R)-4-[2-cyano-5-(3-pyridylmethoxy)phenoxy]-4-(2-methylphenyl)b utanoi c acid (12m). This compound exhibits low-nanomolar binding to the ETA receptor and a greater than 1000-fold selectivity over the ETB receptor. Data are presented to demonstrate that 12m is orally bioavailable in the rat and is a functional antagonist in vitro and in vivo of ET-1-induced vasoconstriction.

CiteXplore: 9667964

DOI: 10.1021/jm9707131