Discovery of 3-Methyl-<i>N</i>-(1-oxy-3‘,4‘,5‘,6‘-tetrahydro-2‘<i>H</i>-[2,4‘-bipyridine]-1‘-ylmethyl)benzamide (ABT-670), an Orally Bioavailable Dopamine D<sub>4</sub> Agonist for the Treatment of Erectile Dysfunction
作者:Meena V. Patel、Teodozyj Kolasa、Kathleen Mortell、Mark A. Matulenko、Ahmed A. Hakeem、Jeffrey J. Rohde、Sherry L. Nelson、Marlon D. Cowart、Masaki Nakane、Loan N. Miller、Marie E. Uchic、Marc A. Terranova、Odile F. El-Kouhen、Diana L. Donnelly-Roberts、Marian T. Namovic、Peter R. Hollingsworth、Renjie Chang、Brenda R. Martino、Jill M. Wetter、Kennan C. Marsh、Ruth Martin、John F. Darbyshire、Gary Gintant、Gin C. Hsieh、Robert B. Moreland、James P. Sullivan、Jorge D. Brioni、Andrew O. Stewart
DOI:10.1021/jm060662k
日期:2006.12.1
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.