Pharmacokinetic experiments were conducted in male BALB/c mice. No signs of toxicity were observed at either dose (10 mg/kg and 15 mg/kg). Therefore, the 15 mg/kg dose was identified as the no observed adverse effect level (NOAEL). This dose was used in the pharmacokinetic study, and no signs of toxicity were observed again. The macroscopic examination revealed no abnormalities in the intraperitoneal cavity (administration site), kidneys, or liver. These findings were consistent with histopathological observations, where all renal samples (including controls) exhibited increased glomerular epithelial thickness, indicative of the young age of the experimental animals. Similarly, in the liver, anisocytosis and residual hematopoiesis were observed. No other pathological changes were detected.Following intraperitoneal (i.p.) administration, the compound 5m was successfully detected in the plasma and brain (Figure ). The experimental data were analyzed using standard noncompartmental analysis in PKanalix (v. 2024R1), and the results are summarized in Table . Compound 5m exhibited simple pharmacokinetics, with a single peak in both plasma and brain. The compound was actively transported across the BBB, with a brain-to-plasma ratio (calculated from AUC0-120) of 2.36. Coefficient. All values are expressed as mean ± SEM of four independent measurements.