Amphiphilic n-oligoethyleneglycol-imidazolium derivatives of p-tert-butylthiacalix[4]arene: Synthesis, aggregation and interaction with dna

Abstract

New water-soluble derivatives of p-tert-butylthiacalix[4]arene have been synthesized in the stereoisomeric form 1,3-alternate with butyl and tetradecyl groups on one side of the macrocyclic platform and tri/tetraethylene glycol substituents on the other. The aggregation characteristics of macrocycles in the aquatic environment (CAC, aggregate size, zeta potential) have been studied. It has been demonstrated that the resulting aggregates have the ability to solubilize the lipophilic azo dye Orange OT, and the solubilizing ability significantly increases on going from butyl to tetradecyl derivatives. Using the methods of dynamic and electrophoretic light scattering and fluorimetry with ethidium bromide as a probe, it was shown that the obtained macrocycles interact with the DNA of the calf thymus. It was found that the efficiency of the interaction is greatly influenced by the length of the oxyethyl fragments: macrocycles containing tetraethylene glycol fragments are more effective than triethylene glycol analogs, causing a 2-fold compaction of DNA.