Abstract
Thirteen sulfonylurea derivatives were synthesized and their binding with bovine serum albumin was investigated, using an equilibrium dialysis technique. The Scatchard plots for data of 11 sulfonylurea derivatives indicated the presence of more than two classes of a binding site. The binding parameters, k1, k2, n1, and n2 were computed by the principle of least squares method. Physicochemical properties such as the dissociation constant in water and partition coefficient with octanol-water system were obtained. With the use of Hansh analysis, BSA binding constants could be represented as follows : For the binding constant at the primary site, log k1=0.512 log P+3.754, binding constant at the secondary site, log k2=0.334 log P+0.240 pKa+1.480. An important role of hydrophobicity must be considered for binding at the primary site, but electrostatic force as well as hydrophobic force must also be included for binding at the secondary site.
