7ETMC is a selective Human Cytochrome P450s 1A1 and 1A2 inhibitor. 7ETMC showed IC50s of 0.46 μM and 0.50 μM for P450s 1A1 and 1A2 in the first six minutes, respectively, and did not show any inhibition activity for P450s 2A6 and 2B1 even at the dose of 5