A macrocyclic receptor based on a bischromenylurea and an α, α'-(o, o'-dialkyl) diphenyl-p- xylylenediamine spacer provides a C 2 chiral cavity to associate carboxylates by H-bonds. The extent of the selectivity obtained for the racemic receptor 2 and enantiomerically pure (S)-naproxen is 7.2: 1. Steric repulsions close to the cavity are decisive for the chiral selectivity.