Synthesis and Biological Activity of Flurbiprofen Analogues as Selective Inhibitors of β-Amyloid1-42 Secretion
摘要:
Flurbiprofen, a nonsteroidal antiinflammatory drug (NSAID), has been recently described to selectively inhibit beta-amyloid(1-42) (A beta 42) secretion, the most toxic component of the senile plaques present in the brain of Alzheimer patients. The use of this NSAID in Alzheimer's disease (AD) is hampered by a significant gastrointestinal toxicity associated with cyclooxygenase (COX) inhibition. New flurbiprofen analogues were synthesized, with the aim of increasing A beta 42 inhibitory potency while removing anti-COX activity. In vitro ADME developability parameters were taken into account in order to identify optimized compounds at an early stage of the project. Appropriate substitution patterns at the alpha position of flurbiprofen allowed for the complete removal of anti-COX activity, while modifications at the terminal phenyl ring resulted in increased inhibitory potency on A beta 42 secretion. In rats, some of the compounds appeared to be well absorbed after oral administration and to penetrate into the central nervous system. Studies in a transgenic mice model of AD showed that selected compounds significantly decreased plasma A beta 42 concentrations. These new flurbiprofen analogues represent potential drug candidates to be developed for the treatment of AD.
A series of 2-[4-(thiazol-2-yl)phenyl]propionic acids substituted at various positions were prepared by the reaction of diethyl 2-methyl-2-(4-thiocarbamoylphenyl)malonates with alpha-bromoaldehyde diethyl acetals or alpha-haloketones followed by hydrolysis of esters. The inhibition of prostaglandin H synthetase (cyclooxygenase) was assayed by use of an enzyme preparation from guinea pig polymorphonuclear