Thermodynamics of molecular recognition by cyclodextrins. 1. Calorimetric titration of inclusion complexation of naphthalenesulfonates with .alpha.-, .beta.-, and .gamma.-cyclodextrins: enthalpy-entropy compensation

Calorimetric titrations have been performed at 25 o C in buffered aqueous solution (pH 7.20) to give the complex stability constants and the thermodynamic parameters for the inclusion complexation of naphthalenesulfonates 1-6 and naphthaleneacetate 7 with α-, β-, and γ-cyclodextrins (CDs). Data analyses assuming 1:1 stoichiometry were successfully applied to all of the host-guest combinations employed, except for the inclusion of 2-naphthalenesulfonate 2 with γ-CD, where both 1:1 and 1:2 host-guest complex formations were observed