New 2H-chromene-3-carboxamide derivatives: design, synthesis and use as inhibitors of hMAO.

A series new 2H-chromene-3-carboxamide derivatives 4a-4t were synthesized and evaluated as monoamine oxidase A and B (MAO-A and MAO-B) inhibitors. Among them, compound 4d (IC50 = 0.93 μM, IC(50 iproniazid) = 7.80 μM) showed the most activity and higher MAO-B selectivity (64.5-fold vs. 1-fold) with respect to the MAO-A isoform. The active compound 4d was also docked into the hMAO-B complex structure active site to determine the probable binding model. The results indicated that conserved residue CYSA 172 was important for ligand binding via hydrogen bond interaction, Pi-Pi interaction was found between the benzene-ring of compound 4d and residue ILEA 199.