Metabolic transformation
Five metabolites of AD16 were identified in plasma, urine, and fecal samples, which were speculated to be mainly mediated by oxidation, hydrolysis, N-dealkylation, glucuronic acid binding, and sulfonic acid reaction. After oral administration of AD16 tablets, little AD16 was excreted in urine and feces. Cumulative excretion of AD16 in urine accounted for 0.17% of the administered dose (Additional file 