In comparing N-phenyl compounds (5-8) with compound 4 (Table S1), it was found that compound 8 showed higher values of Mor04m (1.499), Mor08e (-0.478) and H8m (0.021) but a lower G1v value (0.169) than the most potent compound 4 (Mor04m = 1.104, Mor08e = -0.728, H8m = 0.002 and G1v = 0.190). Similar effects were noted for compounds 5-7, which showed higher Mor04m, Mor08e and H8m values but lower G1v values than compound 4. Such high values of mass (Mor04m and H8m) and electronegativity (Mor08e) descriptors could be due to the effects of substituents (R= NHPh, COCH3, and CO2H) on the Ph ring of secondary amines (5-8), and lower values of van der Waals volume were observed when comparing with the tertiary amine 4. Among the compounds 5-8, the one with an electron-donating group at the para-position (8, R = NHPh) had a lower Mor08e value (-0.478) compared to that with an electron-withdrawing group at the para-position (7, R = COCH3, Mor08e = -0.280). Compound 6, with R (COCH3) at the meta-position, showed a lower Mor08e value (-0.642) compared with its para-isomer (7). For the ortho-CO2H group (R) of compound 5, a higher Mor08e value (-0.182) was observed. The results suggest that the electronic effects of R groups provided a Mor08e value that is well correlated with the activity, in which a lower Mor08e value yielded a higher activity for the compounds, as noted for compounds 8 > 6 > 7 > 5 (Table S1).