Inhibitors of β-Site Amyloid Precursor Protein Cleaving Enzyme (BACE1): Identification of (<i>S</i>)-7-(2-Fluoropyridin-3-yl)-3-((3-methyloxetan-3-yl)ethynyl)-5′<i>H</i>-spiro[chromeno[2,3-<i>b</i>]pyridine-5,4′-oxazol]-2′-amine (AMG-8718)
作者:Thomas A. Dineen、Kui Chen、Alan C. Cheng、Katayoun Derakhchan、Oleg Epstein、Joel Esmay、Dean Hickman、Chuck E. Kreiman、Isaac E. Marx、Robert C. Wahl、Paul H. Wen、Matthew M. Weiss、Douglas A. Whittington、Stephen Wood、Robert T. Fremeau、Ryan D. White、Vinod F. Patel
DOI:10.1021/jm5012676
日期:2014.12.11
We have previously shown that the aminooxazoline xanthene scaffold can generate potent and orally efficacious BACE1 inhibitors although certain of these compounds exhibited potential hERG liabilities. In this article, we describe 4-aza substitution on the xanthene core as a means to increase BACE1 potency while reducing hERG binding affinity. Further optimization of the P3 and P2' side chains resulted in the identification of 42 (AMG-8718), a compound with a balanced profile of BACE1 potency, hERG binding affinity, and Pgp recognition. This compound produced robust and sustained reductions of CSF and brain A beta levels in a rat pharmacodynamic model and exhibited significantly reduced potential for QTc elongation in a cardiovascular safety model.