Since the discovery of bambus[6]uril in 2010, significant progress has been made in the synthesis of bambusuril homologs, BU[n] n=4,6, and their derivatives. These systems have been studied for various applications, especially in the series of all-oxygen BU[6] macrocycles, due to their ability to form strong host-guest complexes with a wide range of anions both in organic and aqueous phases, depending on the type of substituents on their external rims.[1]
Here we present our predictions that heteroatom replacement in glycoluril and bambusuril analogs could significantly alter their molecular electrostatic potential and offer novel opportunities in selective anion binding and transport.[2] Motivated by these predictions we show the synthetic efforts to achieve these molecules. Thus, the structural diversity of bambusurils are presented alongside with the multifaceted binding properties pertaining to these unique cavitands.
In this presentation we highlight three major applications that result from our studies: (i) the sulfur analogs of BU exhibit a double function: they strongly bind a broad variety of anions in their interiors and metal ions at their sulfur edged portals,[3] (ii) nitrogen analogs of BU[6] allow multiple anion binding, and may also function as a unique anion channels,[4] and (iii) semithio-BU[6] acts as a selective transmembrane chloride transporter without pH disruption, which may be used in treatment of channelopathies.[5]
References
[1]. (a) J. Svec, M. Necas, V. Sindelar. Angew. Chem. Int. Ed. 2010, 49, 2378; (b) V. Havel, V. Sindelar, ChemPlusChem. 2015, 80, 1601; (c) V. Havel, M. Babiak, V. Sindelar, Chem-Eur. J. 2017, 23, 8963.
[2]. E. Solel, M. Singh, O. Reany, E. Keinan, Phys. Chem. Chem. Phys. 2016, 18, 13180.
[3]. M. Singh, E. Solel, E. Keinan, O. Reany, Chem. Eur. J., 2015, 21, 536.
[4]. M. Singh, E. Solel, E. Keinan, O. Reany, Chem.-Eur. J. 2016, 22, 8848
[5]. C. Lang, A. Mohite, X. Deng, F. Yang, Z. Dong, J. Xu, J. Liu, E. Keinan, O. Reany Chem. Commun. 2017, 53, 7557