Attempts to separate the enantiomers of the novel adenosine antagonist N-0861, the racemic mixture of N-6-( endo-2-norbornyl)-9-methyladenine, by high-performance liquid chromatography are described. Owing to the very low efficiency and the lack of selectivity of the α-AGP column, the direct separation method did not give satisfactory results. The indirect separation method involved derivatization of N-0861 with (+)-1-(9-fluorenyl)ethylchloroformate. The method is easy to perform and aqueous solutions can be used. The calibration graphs showed that the reaction is linear. A resolution between the formed diastereoisomers of 1.13 within 30 min was obtained on a C 8 column with an acetonitrile—water eluent. The identities of the reaction products were checked by LC—MS.