METHOD FOR SEPARATION OF DISSOLVED L-DIHYDROOROTIC ACID FROM SOLUTION, METHOD FOR PREPARING DIAGNOSTIC AGENT FOR DETERMINATION OF ACTIVITY OF ITS INHIBITORS AND METHOD FOR MONITORING THIS ACTIVITY Russian patent published in 2004 - IPC

FIELD: biochemistry, biochemical technology. SUBSTANCE: invention relates to method for separation of L-dihydroorotic acid by chromatography from the solution containing indicated acid and impurity substances. Method involves the following stages: a) charging indicated solution into chromatography column containing pressure-resistant anion-exchange resin for binding the indicated acid; b) elution of large part of impurity substances from column with an aqueous solution; c) elution of the indicated acid from indicated anion-exchange resin with a base-containing an aqueous solution, for example, sodium hydroxide under pressure from about 1.1 MPa to about 40 MPa, but preferably from about 4.1 MPa to about 5.5 MPa. As a rule, the anion-exchange resin is taken, for example, among divinylbenzene/ethylvinyl-benzene polymer, polyvinylbenzyl ammonium polymer cross- -linked with divinylbenzene and others. As a rule, the concentration of a base in eluting solution is elevated during eluting column and L-dihydroorotic acid is detected in eluate using the conductivity detector. Proposed method can be used in assay in vitro and in vivo of activity of N-(4-tritrifluoromethylphenyl)-5-methylisoxazole-4- carboxamide, N-(4-trifluoromethylphenyl)-2-cyano-3-hydroxycrotone amide and similar compounds. Invention relates also to method for preparing diagnostic analytical agent for determination of activity of dihydroorotate dehydrogenase inhibitors taken, for example, among above indicated compounds and to method for monitoring activity of dihydroorotate dehydrogenase inhibitors using the indicated method for separation of L-dihydroorotic acid wherein activity of inhibitors is determined by the concentration of L- dihydroorotic acid. EFFECT: improved separating and preparing methods. 9 cl, 15 tbl, 3 ex