Pharmacokinetic study of a new 1,2,4-oxadiazine derivative in rat

Pharmacokinetics of 3-phenyl-6-(1, 2, 3, 4-tetrahydro-2-isoquinolyl)-methyl-4H-5,6-dihydro-1,2,4, -oxadiazine (I) in rat were studied. Plasma levels following a single oral dose were determined by HPLC method. Basic plasma samples were partitioned with chloroform. The organic layers were evaporated to dryness under reduced pressure. The residues were redissolved in chloroform and chromatographed on a microporous silica column with chloroform-isopropanol (7:3) eluent. Pharmacokinetics of (I) obeyed the one-compartment open model adequately. Constructed the plasma level curve, absorption and elimination rate constants were calculated by linear regression analysis. Rate of absorption proved to be significantly higher compared to that of elimination. The time of plasma level peak (tmax) was 35 min. After 20 h only traces of (I) could be found in the plasma.