A Vector-Selective Reaction Enables Efficient Construction of Specific Topology upon the Primary Side of β-Cyclodextrin

N-Dansylcysteines attached on the primary side of β-cyclodextrin reacted with the saccharide hydroxyl groups in a vector-selective manner, affording the corresponding lactones. The desired topology of the lactones can be efficiently constructed simply by the selection of the proper enantiomer of d/l-cysteines. In comparison with the exo-lactone, the endo-lactone displayed 4 times stronger fluorescence intensity, stronger binding affinity to sodium adamantanecarboxylate, and 15 times larger signal changes in fluorescence intensity upon binding.