Bambusurils with Fluorinated Substituents – Effects on Binding and Transport Properties


                    Matúš Chvojka,^1,2 Hennie Valkenier,^2 Vladimír Šindelář^1
                                                 ^

^1Department of Chemistry and RECETOX, Masaryk University, Kamenice 5, 62500 Brno, Czech republic.
^2Engineering of Molecular NanoSystems, Université libre de Bruxelles, Avenue F. Roosevelt 50, 1050
                                         Brussels, Belgium

                                   e-mail: mchvojka@mail.muni.cz


Bambusurils are macrocyclic substances made of six glycoluril building units connected via
methylene linkers (Fig. 1).^1 The bambusurils are appreciated for strong anion binding in solution,
which was improved even further by introduction of fluorinated substituents, leading to
exceptionally high association constants ranging between 10^7-10^11 M^-1 in acetonitrile.^2
Appending fluorinated substituents to the bambusurils did also increase lipophilicity and in
combination with high anion binding strength, very efficient bicarbonate/chloride antiporters were
obtained.

In this work, new fluorinated bambusuril derivatives were prepared (Fig. 1). This allowed us to
study the effect of the bambusuril substituents on anion binding strength and anion transport
efficiency of the macrocycles. Preparing derivatives with increasing perfluoroalkyl chain lengths
provided series with increasing lipophilicity. On the other hand, oxidation of the trifluoromethyl
groups of known derivative made the substituents more electron withdrawing, which in turn enhanced
the binding strength.



Fig. 1 Studied bambusuril derivatives


This work was supported by the Czech Science Foundation (reg. No. GA20-13922S) and by FNRS
(Aspirant research fellowship 40006851).


1   Švec, J.; Nečas, M.; Šindelář, V. Angew. Chem. Int. Ed. 2010, 49, 2378-2381.

2   Valkenier, H.; Akrawi, O.; Jurček, P.; Sleziaková, K.; Lízal, T.; Bartik, K.; Šindelář, V.,
Chem 2019, 5 (2), 429.