Gas-liquid chromatographic method for the measurement of plasma levels of d-7,8-dimethoxy-3-methyl-phenyl-2,3,4,5-tetrahydro-1h-3-benzazepine acid maleate (SCH-12679) and its major metabolites in aggressive mental retardites

A sensitive gas-liquid chromatographic technique for the quantitative analysis of SCH-12679 (d-7,8-dimethoxy-3-methyl-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine acid maleate) and its major metabolites in plasma of aggressive mental retardates receiving therapeutic doses of the medicament has been developed. The lower limits of detection are 20 ng/ml for SCH-12679, 0.5 ng/ml for 3-desmethyl SCH-12679 and 0.4 ng/ml for 7-desmethyl plus 8-desmethyl SCH-12679. SCH-12679 is estimated with a flame ionization detector. Its metabolites are quantitated using an electron-capture detector after conversion of the compounds to their heptafluorobutyryl derivatives by reaction with the appropriate anhydride. Data on plasma levels of unchanged SCH-12679, 3-desmethyl SCH-12679 and a combination of 7-desmethyl and 8-desmethyl SCH-12679 in fifteen patients treated with the medicament are presented.