Human colon adenocarcinoma-2 cell line (Caco2) permeability and human intestinal absorption (HIA) are key parameters to decide the total bioavailability of a drug. All the five compounds (EGCG, TF2a, TF2b, TF3, and remdesivir) showed comparatively low Caco2 permeability potential (<8 × 10−6 cm/s) and could be absorbed via the human intestine (Larregieu & Benet, 2013). EGCG, TF2a, TF2b, TF3, and remdesivir were predicted to be substrates of permeability glycoprotein (P-glycoprotein), which is an efflux membrane protein. However, remdesivir was predicted as a P-glycoprotein I inhibitor, and EGCG and TF3 as a P-glycoprotein II inhibitor, whereas TF2a and TF2b as both P-glycoprotein I and II inhibitor. Hence, above mentioned five compounds could regulate the physiological functions of P-glycoprotein (see Table S3 in the Supplementary Information).