Novel (Thio)urea Compounds for Anions Binding and
Transmembrane Transport
Jacopo Torrisi,1 Aaron Torres Huerta,2 Hennie Valkenier,2 Vladimír Šindelář*,1
1Department of Chemistry and RECETOX, Faculty of Science, Masaryk University,
Kamenice 5, 625 00 Brno, Czech Republic, 2Université Libre de Bruxelles,
Engineering of Molecular NanoSystems, Ecole Polytechnique de Bruxelles, Avenue
F.D. Roosevelt 50, CP 165/64, 1050 Brussels Belgium
jacopo.torrisi@mail.muni.cz
Ureas have found widespread use in diverse areas of chemistry as anion receptors,
sensors, and gelling agents, as well as in the fields of molecular recognition and
biological applications such as transmembrane anion transport.1,2 Many urea
applications are possible thanks to their NH groups, which are capable of strong Hbonding
interactions. The strength of these interactions could be modulated by the
choice of functional groups attached to the nitrogen atoms of ureas. In this work, we
decided to explore ureas containing fluorinated substituents, which should show
enhanced affinities towards anions and the lipophilicity at the same time.
We synthesized several urea compounds bearing phenyl rings with trifluoromethyl
sulfides moieties and their oxidized derivatives. Subsequently, benzyl analogues of the
ureas and the corresponding thioureas were also synthesized. Supramolecular
properties of these ureas, such as the anion recognition ability, were tested through
NMR, UV-vis and ITC techniques. The urea compounds were also investigated for their
ability to transport anions through lipophilic membrane using artificial unilamellar
vesicles in conjunction with fluoresce spectroscopy. Lucigenin assay was used to
monitor the transport of chloride, and the 8‐hydroxypyrene‐1,3,6‐trisulfonate assay
was used to monitor changes of pH originating from transport of protons or hydroxide.
1 Busschaert, N.; Kirby, I.L.; Young, S.; Coles, S.J.; Horton, P.N.; Light, M.E. and Gale,
P.A. Angew. Chem. Int. Ed. 2012, 51: 4426-4430.
2 Boiocchi, M.; Del Boca, L.; Gómez, D.E.; Fabbrizzi, L.; Licchelli, M. and Monzani,
E. Journal of the American Chemical Society 2004, 126 (50), 16507-16514.