Anions molecular

Dowex 1-X4 1.0 0.70 Strongly basic anion exchanger with S-DVB matrix for separation of organic acids, nucleotides, phosphoinositides, and other anions. Molecular weight exclusion is <1400. 

Houk RJT, Tobey SL, Anslyn EV (2005) Abiotic Guanidinium Receptors for Anion Molecular Recognition and Sensing. 255 199-229 Hue I, see Brizard A (2005) 256 167-218... 

Anions play key roles in chemical and biological processes. Many anions act as nucleophiles, bases, redox agents or phase transfer catalysts. Most enzymes bind anions as either substrates or cofactors. The chloride ion is of special interest because it is crucial in several phases of human biology and in disease regulation. Moreover, it is of great interest to detect anionic pollutants such as nitrates and phosphates in ground water. Design of selective anion molecular sensors with optical or electrochemical detection is thus of major interest, however it has received much less attention than molecular sensors for cations. 

The methods of anion detection based on fluorescence involve quenching, complex formation, redox reactions and substitution reactions (Fernandez-Gutierrez and Munoz de la Pena, 1985). This chapter will be restricted to anion molecular sensors based on collisional quenching (in general, they exhibit a poor selectivity) and on recognition by an anion receptor linked to a fluorophore (fluoroionophore). 

Krause et al. thus believed that a correlation existed between anion molecular weight and their protective abilities, although the complete mechanism is not clear. 

Houk RJT, Tobey SL, Anslyn EV (2005) Abiotic Guanidinium Receptors for Anion Molecular... 

Figure 1.2 Structure of a Ptsg anionic molecular cluster [19], (With the permission ofG. Longoni.)...

Richardson NA, Gu J, Wang S, Xie Y, Schaefer HF III (2004) DNA nucleosides and their radical anions molecular structures and electron affinities. J Am Chem Soc 126 4404-4411 Riederer FI, Fluttermann J (1982) Matrix isolation of free radicals from 5-halouracils. 3. Electron spin resonance of base oxidation in aqueous acidic glasses. J Phys Chem 86 3454-3463 Riederer FI, Fluttermann J, Symons MCR (1978) cr -Electron addition to 5-halogenouracils in neutral glasses. J Chem Soc Chem Commun 313-314... 

Houk RJT, Tobey SL, Anslyn EV (2005) Abiotic Guanidinium Receptors for Anion Molecular Recognition and Sensing. 255 199-229 IshiiA, Nakayama J (2005) Carbodithioic Acid Esters. 251 181-225 Ishii A, Nakayama J (2005) Carboselenothioic and Carbodiselenoic Acid Derivatives and Related Compounds. 251 227-246 Jones W, see Trask AV (2005) 254 41-70 Kambe N, see Fujiwara S-i (2005) 251 87-140... 

The cyanometalate box Cs c [Cp Rh(CN)3]4[Mo(CO)3]4 3 is formed in low yield from the reaction of [Cp Rh(CN)3] (Cp = CsMes) and (/ -CeHtMet )Mo(CO)3 in the presence of cesium ions, and it can be crystallized as a Et4N+ salt. The Cs+ ion serves as a template in the self-assembly of the anionic molecular box, which has a cubic Rh4Mo4(/r-CN)i2 core with three exterior carbonyl ligands attached to each Mo and a Cp group to each Rh. The encapsulated Cs+ ion has a formal coordination number of 12 if interaction with the centers of cyano groups is considered (Fig. 20.3.15). 

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