Publications by authors named "Timothy S Powers"

BACE1 inhibition to prevent Aβ peptide formation is considered to be a potential route to a disease-modifying treatment for Alzheimer's disease. Previous efforts in our laboratory using a combined structure- and property-based approach have resulted in the identification of aminooxazoline xanthenes as potent BACE1 inhibitors. Herein, we report further optimization leading to the discovery of inhibitor 15 as an orally available and highly efficacious BACE1 inhibitor that robustly reduces CSF and brain Aβ levels in both rats and nonhuman primates.

View Article and Find Full Text PDF

The β-site amyloid precursor protein (APP) cleaving enzyme 1 (BACE1) is one of the most hotly pursued targets for the treatment of Alzheimer's disease. We used a structure- and property-based drug design approach to identify 2-aminooxazoline 3-azaxanthenes as potent BACE1 inhibitors which significantly reduced CSF and brain Aβ levels in a rat pharmacodynamic model. Compared to the initial lead 2, compound 28 exhibited reduced potential for QTc prolongation in a non-human primate cardiovascular safety model.

View Article and Find Full Text PDF

Osteoarthritis (OA) is a nonsystemic disease for which no oral or parenteral disease-modifying osteoarthritic drug (DMOAD) is currently available. Matrix metalloproteinase 13 (MMP-13) has attracted attention as a target with disease-modifying potential because of its major role in tissue destruction associated with OA. Being localized to one or a few joints, OA is amenable to intra-articular (IA) therapy, which has distinct advantages over oral therapies in terms of increasing therapeutic index, by maximizing drug delivery to cartilage and minimizing systemic exposure.

View Article and Find Full Text PDF

Using fragment-based screening of a focused fragment library, 2-aminoquinoline 1 was identified as an initial hit for BACE1. Further SAR development was supported by X-ray structures of BACE1 cocrystallized with various ligands and molecular modeling studies to expedite the discovery of potent compounds. These strategies enabled us to integrate the C-3 side chain on 2-aminoquinoline 1 extending deep into the P2' binding pocket of BACE1 and enhancing the ligand's potency.

View Article and Find Full Text PDF

Objective: Matrix metalloproteinases (MMPs) have long been considered excellent targets for osteoarthritis (OA) treatment. However, clinical utility of broad-spectrum MMP inhibitors developed for this purpose has been restricted by dose-limiting musculoskeletal side effects observed in humans. This study was undertaken to identify a new class of potent and selective MMP-13 inhibitors that would provide histologic and clinical efficacy without musculoskeletal toxicity.

View Article and Find Full Text PDF

Active polymerization catalysts, novel resin-bound diimine complexes of nickel(II) and palladium(II) are obtained by combinatorial synthesis and combined in a catalyst library. By tagging with fluorescent markers, the catalysts can be coded. Therefore, after cleavage of the tag from the polymer-coated resin, HPLC can be used to determine the pathway along which the products were formed.

View Article and Find Full Text PDF