Document Report Card

ID: ALA1137302

Journal: J Med Chem

Title: Discovery of 3-methyl-N-(1-oxy-3',4',5',6'-tetrahydro-2'H-[2,4'-bipyridine]-1'-ylmethyl)benzamide (ABT-670), an orally bioavailable dopamine D4 agonist for the treatment of erectile dysfunction.

Authors: Patel MV, Kolasa T, Mortell K, Matulenko MA, Hakeem AA, Rohde JJ, Nelson SL, Cowart MD, Nakane M, Miller LN, Uchic ME, Terranova MA, El-Kouhen OF, Donnelly-Roberts DL, Namovic MT, Hollingsworth PR, Chang R, Martino BR, Wetter JM, Marsh KC, Martin R, Darbyshire JF, Gintant G, Hsieh GC, Moreland RB, Sullivan JP, Brioni JD, Stewart AO.

Abstract: The goal of this study was to identify a structurally distinct D(4)-selective agonist with superior oral bioavailability to our first-generation clinical candidate 1a (ABT-724) for the potential treatment of erectile dysfunction. Arylpiperazines such as (heteroarylmethyl)piperazine 1a, benzamide 2, and acetamides such as 3a,b exhibit poor oral bioavailability. Structure-activity relationship (SAR) studies with the arylpiperidine template provided potent partial agonists such as 4d and 5k that demonstrated no improvement in oral bioavailability. Further optimization with the (N-oxy-2-pyridinyl)piperidine template led to the discovery of compound 6b (ABT-670), which exhibited excellent oral bioavailability in rat, dog, and monkey (68%, 85%, and 91%, respectively) with comparable efficacy, safety, and tolerability to 1a. The N-oxy-2-pyridinyl moiety not only provided the structural motif required for agonist function but also reduced metabolism rates. The SAR study leading to the discovery of 6b is described herein.

CiteXplore: 17149874

DOI: 10.1021/jm060662k