2.B.26 The Bis(imidazolyl) or (guanidino)-functionalized Bis(Choloyl) Conjugate (BCC) Family
A bis(imidazolyl)-functionalized bis(choloyl) conjugate was synthesized and assessed for its transmembrane anionophoric activity by means of the chloride ion selective electrode technique and pyranine assays (Li et al. 2016). This conjugate mediated the symport of a proton and an anion. It was found to exhibit much higher anionophoric activity than the analogue without imidazolyl groups, revealing a role of the imidazolyl groups in the anion transport process.
A rigid bis(choloyl) conjugate functionalized with guanidino groups has been synthesized and fully characterized on the basis of NMR (1H and 13C) and ESI MS (LR and HR) data. Its transmembrane ionophoric activity across egg-yolk l-α-phosphatidylcholine-based liposomal membranes was investigated by means of chloride ion selective electrode technique and pH discharge assay (Deng et al. 2015). The data indicated that under the assay conditions used, this conjugate was capable of promoting the transport of anions, presumably via a cation/anion symport process. A Hill analysis reveals that two molecules of this compound are assembled into the transport-active species.