Hubert Josien

The discovery of fused oxadiazepines as gamma secretase modulators for treatment of Alzheimer’s disease

In an attempt to further improve overall profiles of the oxadiazine series of GSMs, in particular the hERG activity, conformational modifications of the core structure resulted in the identification of fused oxadiazepines such as 7i which had an improved hERG inhibition profile and was a highly efficacious GSM in vitro and in vivo in rats. These SAR explorations offer opportunities to identify potential drugs to treat Alzheimers disease.

Design and synthesis of tricyclic sulfones as γ-secretase inhibitors with greatly reduced Notch toxicity

A novel series of tricyclic gamma-secretase inhibitors was designed and synthesized via a conformational analysis of literature compounds. The preliminary results have shown that compounds in this new series have much improved in vitro potency and in vivo profiles. More importantly, they have greatly reduced Notch related toxicity that was associated with previous gamma-secretase inhibitors.

Structure activity relationship studies of tricyclic bispyran sulfone γ-secretase inhibitors.

An investigation is detailed of the structure activity relationships (SAR) of two sulfone side chains of compound (-)-1a (SCH 900229), a potent, PS1-selective γ-secretase inhibitor and clinical candidate for the treatment of Alzheimers disease. Specifically, 4-CF(3) and 4-Br substituted arylsulfone analogs, (-)-1b and (-)-1c, are equipotent to compound (-)-1a. On the right hand side chain, linker size and terminal substituents of the pendant sulfone group are also investigated.

Iminopyrimidinones: A novel pharmacophore for the development of orally active renin inhibitors

The development of renin inhibitors with favorable oral pharmacokinetic profiles has been a longstanding challenge for the pharmaceutical industry. As part of our work to identify inhibitors of BACE1, we have previously developed iminopyrimidinones as a novel pharmacophore for aspartyl protease inhibition. In this letter we describe how we modified substitution around this pharmacophore to develop a potent, selective and orally active renin inhibitor.

Substituted 4-morpholine N-arylsulfonamides as γ-secretase inhibitors.

The design, synthesis, SAR, and biological profile of a substituted 4-morpholine sulfonamide series of γ-secretase inhibitors (GSIs) were described. In several cases, the resulting series of GSIs reduced CYP liabilities and improved γ-secretase inhibition activity compared to our previous research series. Selected compounds demonstrated significant reduction of amyloid-β (Aβ) after acute oral dosing in a transgenic animal model of Alzheimers disease (AD).