Abstract: Three new drugs, penequinine, bencynonate and kemadrine, have been baseline separated by reversed phase-HPLC using β-cyclodextrin as chiral mobile phase additive, whereas HPLC with β-cyclodextrin chiral stationary phase can only be used to baseline separate bencynonate. Binding constants, stoichiometry ratios and separation factors have been used to evaluate chiral recognition mechanism. Analyte retention mechanism is consistent with β-cyclodextrin inclusion hydrophobic models of interaction. Adding triethylamine to the mobile phase and decreasing pH can improve peak symmetry and reduce retention. Structural factors affecting chiral recognition and separation of β-cyclodextrin for 8 multiring compounds have been discussed.