[The separation of some racemic beta-blockers and alpha-sympathomimetics with HPLC following derivatization]

Five beta-adrenergic blocking agents and two alpha-sympathicomimetics were separated after derivatization with (R)-(-)-1-(Naphth-1-yl)-ethylisocyanate (NEIC). For two of these analytes the separation was successful also after reaction with (R)-(+)-1-phenylethylisocyanate (PEIC) by using HPLC with RP-18 phases and a water-methanolic eluent by UV-detection on 254 nm. After reaction with (1S)-(+)-campher-10-sulfonylchloride (CSC) an acceptable separation of norphenylephedrine also was possible. Analytes which can be derivated with NEIC and PEIC give no reaction with CSC (and vice versa).