Towards Synthetic Adrenaline Receptors

Abstract

The macrocyclic bisphosphonate 2 forms complexes with amino alcohols, amines, and amino acid esters with high association constants in polar organic solvents. Exertion of solvophobic interactions inside the macrocyclic cavity in DMSO and methanol leads to specificity for guest molecules with hydrophobic moieties. Experimental evidence is presented for the insertion of the guest molecules' nonpolar groups into the macrocycle's hydrophobic cavity. NMR spectra of complexes with 2 in DMSO show a molecular imprint of the guest molecule; this gives information about its location inside the macrocycle. In aqueous solutions strong self-association of 2 occurs, which is explained by distinct structural similarities between 2 and micelle-forming phospholipids.

A fluorescent cyclotriveratrylene: synthesis, emission properties and acetylcholine recognition in water

“…14 Chemical shift variations were examined to determine the nature of this host-guest association. 15 1 H NMR signals of ACh showed a small modification at its ammonium extremity (Dd max ª -0.06 ppm for CH 3 N + and CH 2 N + ) which is consistent with a weak cationic interaction with 1 (Table 1). Considering 1, the n-butyl group protons H a-d were shifted (Table 1, Dd max from +0.11 to +0.31 ppm respectively).…”

Molecular recognition of organic ammonium ions in solution using synthetic receptors

“…The recognition with para- xylene-bisphosphonates was shown with several examples of ammonium [540–541] and guanidinium [528,542] cations by Schrader et al Similarly, the group demonstrated the recognition of the amidinium ion with the simple m -xylene bisphosphonate 159 .…”

Synthetic receptors

“…Schrader has made progress towards the binding of small biologically important molecules with his bisphosphonate based receptors. [188][189][190][191][192] Those containing a xylene core with one or two pendent phosphonate moieties (Fig. 24) display significant binding to 1,2-and 1,3-amino alcohols 188,190 and amino sugars, 191 whilst receptors with a biaryl core are large enough to bind alkylguanidinium species.…”