C_3v Symmetric Receptors Show High Selectivity and High Affinity for Phosphate

Abstract

The binding of phosphate to tripodal metalloreceptors 1 and 2 is reported. Receptors 1 and 2 are C3v symmetric, designed to complement three sides of a tetrahedron. The receptors derive from tripodal ligands that are preorganized through binding to a central Cu(II) atom. These metalloreceptors demonstrate high selectivity and affinity for the molecular recognition of phosphate in aqueous media at neutral pH. The binding of phosphate and other anions to the cavities of receptors 1 and 2 was monitored by UV/vis titration techniques. Binding algorithms were used to determine the affinity of phosphate to 1 and 2 with association values (Ka) of 2.5 x 104 and 1.5 x 104 M-1, respectively.

Supramolekulare Chemie in Wasser

“…[48][49][50] [50] und er zeigt eine sehr hohe Selektivität für Monoalkylphosphate (K a % 1-3 10 5 m À1 in 10 mm HEPES, pH 7.2) [50] gegenüber Dialkylphosphaten (unmessbar klein), [48,50] ). [52,53] Der Rezeptor 20 fand Anwendung in einem Indikatorverdrängungsassay zur Bestimmung der Phosphatkonzentrationen in Pferdeserum und menschlichem Speichel bei biologischem pH-Wert. [53] Rezeptoren wie 20-22 mit drei Bindungsstellen erkennen und unterscheiden hoch funktionalisierte Gäste effizient.…”

“…So bindet der Rezeptor 21 Propan-1,2,3-tricarboxylat und 1,2,3,4-Butantetracarboxylat in wässriger Lösung (HEPESPuffer, pH 7.4) mit K a % 1.8 10 4 -2.2 10 5 m À1 um 1-3 Grö-ßenordnungen besser als Glutarat und Acetat (K a % 3 10 2 -2 10 3 m À1 ). [54] Eine Reihe modifizierter Triethylbenzolrezeptoren mit Guanidinium-und/oder Boronsäuresubstitu-enten wurde untersucht (22 enthält z. B. zwei 2-Aminoimidazolium-Substituenten und eine intramolekular mit einem Stickstoffatom komplexierte Boronsäurefunktion).…”

Synthesis and structural analyses of phenylethynyl-substituted tris(2-pyridylmethyl)amines and their copper(ii) complexes

“…[22][23][24][25][26][27] Previous work from our group has focused on the use of TPMA derivatives and their metal complexes as sensors for chiral amino acids 28,29 and chiral secondary alcohols, [30][31][32][33][34][35] as well as hosts for phosphate recognition. [36][37][38] Because of their pro-axial chirality and a wide range of use, TPMA and its structural relatives are promising chelators for organometallic materials such as catalysts and chirality sensors. In the process of creating sensors for determining the handedness of various chiral functional groups acting as metal ligands, we generated a series of new TPMA ligands.…”

“Naked‐Eye” Detection of Histidine by Regulation of CuII Coordination Modes

“…Coordinatively unsaturated metal complexes have found wide use in the development of chemosensors, [1][2][3][4] the direction of supramolecular assembly, [5][6][7][8][9] and the study of metalloenzyme function. [10][11][12] As receptors, metal complexes are versatile because they can target a variety of Lewis basic guests through open coordination sites.…”