Structure-Retention Relationship in a Series of Chiral 1,4-Disubstituted Piperazine Derivatives on Carbohydrate Chiral Stationary Phases

New racemic 1,4-disubstituted piperazines chemically named ethyl 2-[(4-pyrimidin-2yl-piperazine-1yl)carbonyl]C3-C5-alkanoates 1-7 were synthesized. The compounds were resolved into enantiomers on cellulose tris(4-methylbenzoate) and amylose tris(3,5-dimethylphenylcarbamate) stationary phases using hexane/propan-2-ol mobile phases. The optimum separation conditions for the compounds were obtained on cellulose tris(4-methylbenzoate) with 5% of 2-propanol in hexane. The relationship between structural and chromatographic parameters is discussed.