Chin. Chem. Lett.

Inclusion of beta-cyclodextrin (beta-CD) with phenothiazine 1 and N-alkylpheno-thiazine derivatives (alkyl = ethyl 2, isobutyl 3 and isopentyl 4) in aqueous solution was studied by means of UV-vis spectroscopy. The association constant K-a values for the inclusion of beta-CD with 1, 2, 3 and 4 were determined to be 188, 214, 129 and 80 L/mol, respectively. It indicates that the stability of the inclusion complexes is dependent on the structure and the volume of the substituents in the guest compounds.Inclusion of beta-cyclodextrin (beta-CD) with phenothiazine 1 and N-alkylpheno-thiazine derivatives (alkyl = ethyl 2, isobutyl 3 and isopentyl 4) in aqueous solution was studied by means of UV-vis spectroscopy. The association constant K-a values for the inclusion of beta-CD with 1, 2, 3 and 4 were determined to be 188, 214, 129 and 80 L/mol, respectively. It indicates that the stability of the inclusion complexes is dependent on the structure and the volume of the substituents in the guest compounds