Enantio- and Substrate-Selective Recognition of Chiral Neurotransmitters with -Symmetric Switchable Receptors.

We report on the synthesis of -symmetric enantiopure cage molecules , which exhibit remarkable to exclusive enantioselective recognition properties toward chiral ammonium neurotransmitters. Strong changes in the substrate selectivity are also observed when different stereoisomers of are used. Furthermore, protonation/deprotonation induces a reversible modification of the conformation of , which switches from an imploded to an inflated form, leading to ejection and reuptake of the guest initially encaged inside the cavity.