Impact of P-glycoprotein-mediated active efflux on drug distribution into lumbar cerebrospinal fluid in nonhuman primates was written by Nagaya, Yoko;Katayama, Kazuhide;Kusuhara, Hiroyuki;Nozaki, Yoshitane. And the article was included in Drug Metabolism & Disposition in 2020.Reference of 144598-75-4 This article mentions the following:
Estimation of unbound drug concentration in the brain (Cu,brain) is an essential part of central nervous system (CNS) drug development. As a surrogate for Cu,brain in humans and nonhuman primates, drug concentration in cerebrospinal fluid (CCSF) collected by lumbar puncture is often used; however, the predictability of Cu,brain by lumbar CCSF is unclear, particularly for substrates of the active efflux transporter P-glycoprotein (P-gp). Here, we measured lumbar CCSF in cynomolgus monkey after single i.v. administration of 10 test compounds with varying P-gp transport activities. The in vivo lumbar cerebrospinal fluid (CSF)-to-plasma unbound drug concentration ratios (Kp,uu,lumbar CSF) of nonsubstrates or weak substrates of P-gp were in the range 0.885-1.34, whereas those of good substrates of P-gp were in the range 0.195-0.458 and were strongly neg. correlated with in vitro P-gp transport activity. Moreover, concomitant treatment with a P-gp inhibitor, zosuquidar, increased the Kp,uu,lumbar CSF values of the good P-gp substrates, indicating that P-gp-mediated active efflux contributed to the low Kp,uu,lumbar CSF values of these compounds Compared with the drug concentrations in the cisternal CSF and interstitial fluid (ISF) that we previously determined in cynomolgus monkeys, the lumbar CCSF were more than triple for two and all of the good P-gp substrates examined, resp. Although lumbar CCSF may overestimate cisternal CSF and ISF concentrations of good P-gp substrates, lumbar CCSF allowed discrimination of good P-gp substrates from the weak and nonsubstrates and can be used to estimate the impact of P-gp-mediated active efflux on drug CNS penetration. In the experiment, the researchers used many compounds, for example, 3-(2-(4-(6-Fluorobenzo[d]isoxazol-3-yl)piperidin-1-yl)ethyl)-9-hydroxy-2-methyl-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-one (cas: 144598-75-4Reference of 144598-75-4).
3-(2-(4-(6-Fluorobenzo[d]isoxazol-3-yl)piperidin-1-yl)ethyl)-9-hydroxy-2-methyl-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidin-4-one (cas: 144598-75-4) belongs to isoxazole derivatives. Isoxazoles also form the basis for a number of drugs, including the COX-2 inhibitor valdecoxib (Bextra) and a neurotransmitter agonist AMPA. Some alternative routes for the synthesis of isoxazoles have also been developed and reported. The 2-benzoyl-2-halo-2H-azirines provide 4-haloisoxazoles in good yields after heating in toluene at reflux temperature.Reference of 144598-75-4
Referemce:
Isoxazole – Wikipedia,
Isoxazole | C3H3NO – PubChem