Monofunctionalized Fluorinated Bambus[6]urils


Nicola Alessandro De Simone,^a Jana Lapešová,^a Matúš Chvojka,^a,b Luis Martínez-Crespo,^b Vladimír
                                  Šindelář,^a Hennie Valkenier^b


                     a. Group of Supramolecular Chemistry, Masaryk university

                              Kamenice 5, 62500 Brno, Czech republic.

              b. Engineering of Molecular NanoSystems, Université libre de Bruxelles,

                          Avenue F. Roosevelt 50, 1050 Brussels, Belgium.

                                    email: matus.chvojka@ulb.be


Bambusurils are macrocyclic substances capable of strong noncovalent interactions with anions. They
are made of six glycoluril building units connected via methylene linkers. Bambusurils are
appreciated for their exceptionally strong anion binding in organic and aqueous solutions, with the
binding affinity to Cl^− ranging up to 6×10^10 M^-1 in acetonitrile [1]. Recently, bambusurils with
one glycoluril unit different from the others were prepared [2]. This allowed to append one unique
functionality per macrocycle for new applications. Here we present a newly developed synthetic
strategy allowing us to prepare fluorinated glycoluril building blocks in higher yields and on
bigger scale. The glycolurils were used in the synthesis of new fluorinated bambusurils.


Anion transport is an important biological process. When it doesn’t work properly in the cells due
to malfunctioning proteins, surviving of the whole organism becomes very difficult. Treatment of
this type of diseases is usually very expensive and limited or often impossible. If certain
criteria are met, anion receptors might be used as anion transporters through lipid bilayers
substituting the function of proteins [3]. Appending fluorinated substituents to the bambusuril
increased lipophilicity and anion binding strength and resulted in very efficient
bicarbonate/chloride antiporters [1]. Herein, the ability of new monofunctionalized bambusuril
derivatives to act as anion transporters was investigated. The derivatives were tested in two
different assays using fluorescence spectroscopy. The lucigenin dye assay was used to detect
chloride transport and the [Eu.L^1]^+-based dye assay [4] was used to detect bicarbonate transport.



References


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