BIIB042, a novel γ-secretase modulator, reduces amyloidogenic Aβ isoforms in primates and rodents and plaque pathology in a mouse model of Alzheimer's disease.

Reducing the production of larger aggregation-prone amyloid β-peptides (Aβ) remains an untested therapeutic approach for reducing the appearance and growth of Aβ plaques in the brain, which are a hallmark pathological feature of Alzheimer's disease. γ-Secretase modulators (GSMs) are therapeutics that impact γ-secretase-dependent cleavage of amyloid precursor protein to promote the production of shorter Aβ peptides that are less prone to aggregation and plaque deposition. This is accomplished without inhibiting overall γ-secretase function and cleavage of other substrates, which is believed to be a source of deleterious side effects.

Discovery of novel pyrazole-containing benzamides as potent RORγ inverse agonists.

The nuclear receptor RORγ plays a central role in controlling a pro-inflammatory gene expression program in several lymphocyte lineages including TH17 cells. RORγ-dependent inflammation has been implicated in the pathogenesis of several major autoimmune diseases and thus RORγ is an attractive target for therapeutic intervention in these diseases. Starting from a lead biaryl compound 4a, replacement of the head phenyl moiety with a substituted aminopyrazole group resulted in a series with improved physical properties.

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 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.

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 Alzheimer's 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.

An inhibitor of NEDD8-activating enzyme as a new approach to treat cancer.

The clinical development of an inhibitor of cellular proteasome function suggests that compounds targeting other components of the ubiquitin-proteasome system might prove useful for the treatment of human malignancies. NEDD8-activating enzyme (NAE) is an essential component of the NEDD8 conjugation pathway that controls the activity of the cullin-RING subtype of ubiquitin ligases, thereby regulating the turnover of a subset of proteins upstream of the proteasome. Substrates of cullin-RING ligases have important roles in cellular processes associated with cancer cell growth and survival pathways.

Design and synthesis of classical and nonclassical 6-arylthio-2,4-diamino-5-ethylpyrrolo[2,3-d]pyrimidines as antifolates.

The classical antifolate N-{4-[(2,4-diamino-5-ethyl-7H-pyrrolo[2,3-d]pyrimidin-6-yl)sulfanyl]benzoyl}-l-glutamic acid (2) and 15 nonclassical analogues (3-17) were synthesized as potential dihydrofolate reductase (DHFR) inhibitors and as antitumor agents. 5-Ethyl-7H-pyrrolo[2,3-d]pyrimidine-2,4-diamine (20) served as the key intermediate to which various aryl thiols and a heteroaryl thiol were appended at the 6-position via an oxidative addition reaction. The classical analogue 2 was synthesized by coupling the benzoic acid derivative 18 with diethyl l-glutamate followed by saponification.