New enantiopure dimethyl-substituted acridino-18-crown-6 and acridino-21-crown-7 ethers containing a carboxyl group at position 9 of the acridine ring [( S,S)- 8, ( S,S)- 9, ( R,R)- 10] were synthesized. The p Ka values of the new crown ethers [( S,S)- 8, ( S,S)- 9, ( R,R)- 10] and of an earlier reported macrocycle [( R,R)- 2] were determined by UV-pH titrations. Crown ether ( S,S)- 8 was attached to silica gel by covalent bonds and the enantiomeric separation ability of the newly prepared chiral stationary phase [( S,S)-CSP- 12] was studied by high-performance liquid chromatography (HPLC). Homochiral preference was observed and the best separation was achieved for the enantiomers of 1-NEA. Ligands ( S,S)- 9 and ( R,R)- 10 are precursors of enantioselective sensor and selector molecules for the enantiomers of protonated primary amines, amino acids, and their derivatives. [ABSTRACT FROM AUTHOR]