ChemistrySelect, cilt.2, sa.13, ss.3854-3859, 2017 (SCI-Expanded)
We describe here the synthesis, antioxidant capacity, and biological activities on MAO, ChE, and selected GPCRs, of novel 1-(2,5-dimethoxybenzyl)-4-arylpiperazines 1–10, as well as known N-(2-(2-methyl-5-nitro-1H-imidazol-1-yl))-2-(4-arylpiperazin-1-yl) 11–20 and N-(5-nitrothiazol-2-yl)-2-(4-arylpiperazin-1-yl) 21–29. Some of the new 4-arylpiperazines were found to have low-micromolar affinities for the proteins tested. The most potent MAO inhibitor identified was compound 2-(4-(3-fluorophenyl)-yl)-N-(5-nitrothiazol-2-yl)(27), with an IC50 value of 4.14 ± 0.5 μM, whereas the most potent interaction with a GPCR was 1-(2,5-dimethoxybenzyl)-4-(4-trifluoromethylphenyl) (5) for the 5-HT6 serotonin receptor, with a Ki value of 0.7 μM. Interestingly, some of the compounds described here showed impressive antioxidant potential. Of mention, compounds 1, 6, 7, and 23 had trolox/equivalent ORAC values of 9.10, 8.80, 8.82, and 9.42, respectively, all of them being significantly higher than the TE determined for ferulic acid (3.74), a standard antioxidant. Among all molecules synthesized and tested, compound 23 can be regarded as an interesting low-micromolar MAO−B/5-HT6 dual inhibitor lead with potent antioxidant properties.