Phosphate anion recognition

Phosphate Anion Recognition Utilizing Coordination Chemistry. . . ... 

Phosphate Anion Recognition Utilizing Coordination Chemistry... 

Nature uses globular protein domains to bind sulfate and phosphate anions using respectively 7 and 12 complementary anion-hydrogen bond arrangements. With this in mind we decided to construct new, neutral ferrocene derivatives that contain various hydrogen bond donor and acceptor sites for anion recognition. 

As a part of our program to develop new adjuvants for the into-cell delivery of phosphorylated nucleotide-type antiviral agents (see Section 3 of this chapter), we became interested in developing a sapphyrin-based approach to phosphate anion chelation. As proved true for halide anion recognition, important initial support for the idea that sapphyrins could function as phosphate anion receptors came from single crystal X-ray diffraction studies. In fact, to date, five X-ray structures of sapphyrin-phosphate complexes have been obtained. ... 

Castellano et al.221 reported the formation of a luminescence lifetime-based sensor for cyanide and other counterions using Ru11 diimines possessing MLCT excited states with the anion recognition capabilities of 2,3-di(l//-2-pyrrolyl)quinoxaline (DPQ). Using time-resolved photoluminescence decay, its viability as a lifetime-based sensor for anions has been tested. There were significant changes to the UV-vis and steady-state emission properties after the addition of several ions (e.g., fluoride, cyanide, and phosphate). 

In 2000 Lee and Hong synthesized tris-thiourea macrocycles 33a and 33b and studied their anion recognition properties by H NMR titration experiments in DMSO-d6 at 25 °C. It was foimd that macrocycle 33a was selective for dihydrogen phosphate (800 M ) over acetate (320 and chloride (40 M ). In contrast macrocycle 33b was foimd to be selective... 

In addition to small molecular phosphate derivatives, phosphate anions having large molecular weight recently emerged as important new subjects in anion recognition research. Hamachi and his co-workers developed... 

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