The development of new approaches of supramolecular chemistry and the identification of the structure–activity relationship is an important and promising problem. Macrocyclic platforms - thiacalix[4]arenes, can be used for the synthesis of compounds with a regulated ability to self-assembly. Due to the ability to fix the macrocyclic ring in several conformations and the relative ease of its functionalization, functional groups can be arranged in a predetermined manner in space. It determines the tendency to self-assembly into nanostructures under the influence of the substrate (ions, molecules).

In this work, we synthesize sulfobetaine derivatives of thiacalix[4]arene in three conformations. In the presence of Ag⁺, these derivatives are capable to self-assemble into associates with different architectures (shapes) and, as a consequence, with cytotoxic selectivity for the cervical carcinoma cell line.

The dynamic light scattering method showed that the synthesized macrocycles in cone, partial cone and 1,3-alternate conformations form submicron-sized particles with Ag⁺ in water, but the particle size and polydispersity of the systems studied depend on the macrocycle conformation. The type of coordination determines the different shapes of the associates. Cytotoxic properties are shown to be controlled by the shape of associates, with the highest activity demonstrated by thiacalix[4]arenes in partial cone conformation.

The work was supported by Russian Science Foundation (№18-73-10094), https://rscf.ru/project/18-73-10094/