Cyclophane-based tetra(resorcinarene) as a host for both histone and hydrophobic molecular guests

A cyclophane-based resorcinarene tetramer, which is constructed with a tetraaza[6.1.6.1]paracyclophane and four resorcinarenes bearing hepta(carboxylic acid) residues that connect the macrocycle through amide linkages, was prepared. The binding constant of the cyclophane-based resorcinarene with immobilized histone was determined to be 1.3 × 107 M−1 by surface plasmon resonance measurements, which was 31-fold larger than that of the resorcinarene monomer bearing octacarboxylic acids. Moreover, the cyclophane-based tetra(resorcinarene) acted as a host toward hydrophobic molecular guests such as 6-p-toluidinonaphthalene-2-sulfonate.