Phosphate ester cleavage

The mechanisms of phosphate ester cleavage vary significantly between monoesters, diesters, and triesters (Thatcher and Kluger, 1989). Each of these is a target for antibody cleavage and progress has been reported for all three cases. 

Steenken S, Behrens G, Schulte-Frohlinde D (1974) Radiation chemistry of DNA model compounds, part IV. Phosphate ester cleavage in radicals derived from glycerol phosphates. Int J Radiat Biol 25 205-210... 

Steenken S, Jagannadham V (1985) Reaction of 6-yl radicals of uracil, thymine, and cytosine and their nucleosides with nitrobenzenes via addition to give nitroxide radicals. OH catalyzed ni-troxide heterolysis. J Am Chem Soc 107 6818-6826 Steenken S, Jovanovic SV (1997) How easily oxidizableis DNA One-electron reduction potentials of adenosine and guanosine radicals in aqueous solution. J Am Chem Soc 119 617-618 Steenken S, Behrens G, Schulte-Frohlinde D (1974) Radiation chemistry of DNA model compounds, part IV. Phosphate ester cleavage in radicals derived from glycerol phosphates. Int J Radiat Biol 25 205-210... 

Stelter L, von Sonntag C, Schulte-Frohlinde D (1976) Phosphate ester cleavage in ribose-5-phos-phate induced by OH radicals in deoxygenated aqueous solution. The effect of Fe(ll) and Fe(lll) ions. Int J Radiat Biol 29 255-269... 

Phosphate ester cleavage can also be achieved with artificial enzymes using both a metal ion and an additional catalytic group, as in the amide and ester hydrolyses described above. In our first example, catalysts 32 and 33 combined a Zn2+ with a thio-phenol and an imidazole group respectively [121]. The rigid structure prevented the... 

Reactive Zn OII (n = 1 or 2) species are proposed in the catalytic cycles of several zinc-containing enzymes. In order to gauge the chemical factors that influence the formation and reactivity of Zn OH species, synthetic model complexes have been prepared and systematically examined for biologically relevant stoichiometric and catalytic reactivity. Systems that promote the hydration of C02, the activation and oxidation of alcohols, and amide and phosphate ester cleavage reactions are discussed. 

One of the hrst synthetic compounds capable of phosphate ester cleavage via a dinuclear metal center was reported in 1984 by Sargeson (Fig. 6.4a) [27]. 

Breslow, R. and Singh, S., Phosphate ester cleavage catalyzed by bifiinctional zinc complexes comments on the p-nitrophenyl ester syndrome , Bioorg. Chem., 1988,16, 408-417. 

Fig. 8.20 Ligands used by Kramer and coworkers to examine secondary H-bonding effects on phosphate ester cleavage [115].

Fig. 8.26 Phosphate ester cleavage reactivity of Ll-L3-ligated zinc complexes [47].

Scrimin, R, Ghirlanda, G., Tecilla, P, Moss, R.A. Comparative reactivities of phosphate ester cleavages hy metallomicelles. Langmuir 1996, 72(26), 6235-6241. 

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