Background
Ligands consisting of two aryl moieties connected via a short spacer were shown to be potent inhibitors of monoamine oxidases (MAO) A and B, which are known as suitable targets in treatment of neurological diseases. Based on this general blueprint, we synthesized a series of 66 small aromatic amide derivatives as novel MAO A/B inhibitors.
Conclusion
The small molecule anilides with different substitution patterns were identified as potent MAO A/B inhibitors, which were active in nanomolar concentrations ranges. These small and easily accessible molecules are promising motifs, especially for newly designed multitargeted ligands taking advantage of these fragments.
Methods
The compounds were synthesized, purified and structurally confirmed by spectroscopic methods. Fluorimetric enzymological assays were performed to determine MAO A/B inhibition properties. Mode and reversibility of inhibition was determined for the most potent MAO B inhibitor. Docking poses and pharmacophore models were generated to confirm the in vitro
Results
N-(2,4-Dinitrophenyl)benzo[d][1,3]dioxole-5-carboxamide (55, ST-2043) was found to be a reversible competitive moderately selective MAO B inhibitor (IC50 = 56 nM, Ki = 6.3 nM), while N-(2,4-dinitrophenyl)benzamide (7, ST-2023) showed higher preference for MAO A (IC50 = 126 nM). Computational analysis confirmed in vitro binding properties, where the anilides examined possessed high surface complementarity to MAO A/B active sites.