Synthesis of the Potent, Selective, and Efficacious β-Secretase (BACE1) Inhibitor NB-360
Journal of Medicinal Chemistry
|April 12, 2021
Summary
Researchers optimized a 1,4-oxazine headgroup to create NB-360, a potent inhibitor of beta-secretase 1 (BACE1). This compound effectively reduces amyloid-beta (Aβ) levels in the central nervous system (CNS) across multiple species.
Area of Science:
- Medicinal Chemistry
- Neuroscience
- Pharmacology
Background:
- Beta-secretase 1 (BACE1) is a key enzyme in amyloid-beta (Aβ) production, a hallmark of Alzheimer's disease.
- Developing potent and brain-penetrant BACE1 inhibitors is crucial for Alzheimer's disease therapeutics.
- Optimization of lead compounds requires careful modification of chemical structures to achieve desired pharmacological profiles.
Purpose of the Study:
- To optimize a lead compound by modifying the 1,4-oxazine headgroup for improved potency and central nervous system (CNS) penetration.
- To investigate synthetic routes for novel BACE1 inhibitors containing a 5-amino-6-methyl-6-(trifluoromethyl)-1,4-oxazine moiety.
- To achieve significant reduction of Aβ levels in preclinical models through structure-activity relationship studies.
Main Methods:
- Structure-based drug design and lead optimization focusing on the 1,4-oxazine headgroup.
- Synthesis and characterization of novel chemical entities targeting BACE1.
- Pharmacokinetic and pharmacodynamic assessments in various animal models (mice, rats, dogs).
Main Results:
- Introduction of methyl and trifluoromethyl groups at the 6-position of the 5-amino-1,4-oxazine improved the pharmacological profile, yielding a pKa of 7.1 and low P-gp efflux.
- Development of efficient synthetic routes for the target BACE1 inhibitors.
- Identification of NB-360 (compound 54) as a highly potent inhibitor that significantly reduced Aβ levels in vivo across multiple species under acute and chronic conditions.
Conclusions:
- The optimized 1,4-oxazine headgroup confers excellent CNS penetration and exposure, crucial for targeting neurological disorders.
- NB-360 demonstrates significant potential as a therapeutic agent for Alzheimer's disease by effectively lowering Aβ burden.
- Further development of NB-360 is warranted based on its potent BACE1 inhibition and favorable pharmacokinetic properties.
