Caged phosphate

Scheme 3.3 Overall photodeprotection reaction of two p-hydroxyphenacyl caged phosphate compounds. See text for more details. (Reprinted in part with permission from reference [49]. Copyright (2006) American Chemical Society.)...

Scheme 3.4 Proposed reaction mechanism for the deprotection and solvolytic rearrangement reactions of pHP caged phosphates like HPDP consistent with the TR, fs-TA and fs-KTRF experiments described here and in references 49 and 134.

By utilizing different probe wavelengths and time-scales, several different intermediates and their reactions were characterized by TR spectroscopy. These results in combination with fs-TA and fs-KTRF experiments provide important kinetics and structural information that enable an overall mechanistic characterization for the photophysical and photochemical events taking place after photolysis of pHP caged phosphates in various solvent environments. 

The development of synchrotron radiation as an X-ray source404 416 418 has permitted accumulation of data for electron density difference maps in less than 1 s and it is expected that such data can eventually be acquired in 1 ps.419-421 If a suitable photochemical reaction can be initiated by a picosecond laser flash, a substrate within a crystalline enzyme can be watched as it goes through its catalytic cycle. An example is the release of inorganic phosphate ions from a "caged phosphate" (Eq. 3-49) and study of the reaction of the released phosphate with glycogen phosphorylase (Chapter 12).422/423... 

Givens, R.S., Athey, P.S., Matuszewski, B., Kueper, L.W. Jill, Xue, J. and Fister, T. (1993) Photochemistry of phosphate esters a-keto phosphates as a photoprotecting group for caged phosphate. Journal of the American Chemical Society, 115, 6001-6012. 

Chart 16. Linear Polymer and Tetrameric Cage Phosphates from the Same Reaction... 

Fang, X. Xu, Y. Ding, T. Synthesis and characterization of cage phosphate microparticles coated with melamine resin based on composite properties of materials. Advanced Materials Research (Dumten-Zurich, Switzerland) (2012), 583 Advanced Composite Materials and Manufacturing Engineering), 236—239. 

The preparation of 2-0-alkyl-ffjyo-inositol-l-phosphates as competitive inhibitors of inositol monophosphataseand the nthesis of myo-inositol-13,5-0-phosphate 109 as a new type of caged phosphate has been reported. 

Caged Phosphate Protection (% Yield) Deprotection (% Yield) ... 

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