Hairuo Peng

Acceleration of Petasis Reactions of Salicylaldehyde Derivatives with Molecular Sieves

Mild reaction conditions for Petasis reactions of substituted salicylaldehydes with various amines and arylboronic acids in the presence of molecular sieves were developed. Molecular sieves (MS) significantly accelerated the reaction rates and drove the reactions to high conversions. The conditions were applied to the synthesis of the core structure of BIIB042, a γ-secretase modulator, without stereochemical erosion of a stereogenic center in the salicylaldehyde intermediate.

Discovery of BIIB042, a Potent, Selective, and Orally Bioavailable γ-Secretase Modulator.

We have investigated a novel series of acid-derived γ-secretase modulators as a potential treatment of Alzheimers disease. Optimization based on cellular potency and brain pharmacodynamics after oral dosing led to the discovery of 10a (BIIB042). Compound 10a is a potent γ-secretase modulator, which lowered Aβ42, increased Aβ38, but had little to no effect on Aβ40 levels both in vitro and in vivo. In addition, compound 10a did not affect Notch signaling in our in vitro assessment. Compound 10a demonstrated excellent pharmacokinetic parameters in multiple species. Oral administration of 10a significantly reduced brain Aβ42 levels in CF-1 mice and Fischer rats, as well as plasma Aβ42 levels in cynomolgus monkeys. Compound 10a was selected as a candidate for preclinical safety evaluation.

Discovery of 4-aminomethylphenylacetic acids as γ-secretase modulators via a scaffold design approach.

Starting from literature examples of nonsteroidal anti-inflammatory drugs (NSAIDs)-type carboxylic acid γ-secretase modulators (GSMs) and using a scaffold design approach, we identified 4-aminomethylphenylacetic acid 4 with a desirable γ-secretase modulation profile. Scaffold optimization led to the discovery of a novel chemical series, represented by 6b, having improved brain penetration. Further SAR studies provided analog 6q that exhibited a good pharmacological profile. Oral administration of 6q significantly reduced brain Aβ42 levels in mice and rats.

Investigating small molecules to inhibit germinal center kinase-like kinase (GLK/MAP4K3) upstream of PKCθ phosphorylation: Potential therapy to modulate T cell dependent immunity

Germinal center kinase-like kinase (GLK, also known as MAP4K3) has been hypothesized to have an effect on key cellular activities, including inflammatory responses. GLK is required for activation of protein kinase C-θ (PKCθ) in T cells. Controlling the activity of T helper cell responses could be valuable for the treatment of autoimmune diseases. This approach circumvents previous unsuccessful approaches to target PKCθ directly. The use of structure based drug design, aided by the first crystal structure of GLK, led to the discovery of several inhibitors that demonstrate potent inhibition of GLK biochemically and in relevant cell lines.