To determine Caco-2 permeability, cells were grown for 10 days at 37°C in an incubator with 5% CO2 and controlled humidity. The assay was performed in a 96-well plate (pH 7.4) in HBSS buffer containing 10 mM HEPES (1% DMSO), and the concentration of compounds was 2 µM (n = 2). Cells were incubated at 37°C for 2.5 h (without shaking) with 5% CO2 and 95% relative humidity. The density of cells was 2.5×10 5 cells/ml. The each concentration of test compound was 2 μM. The detection method was LC-MS/MS. Papp was calculated as Papp = (Va/[area × time]) × (LC-MS area of acceptor sample/LC-MS area of initial donor), where Va = volume of acceptor well (in mL) = 0.25; area = surface area of the membrane (cm 2 ); and time = time of incubation (s) = 9000.