Fluorescent probes photoactivatable

Some miscellaneous methods which may grow in importance deserve a brief review. The potential use of photogenerated reagents in experiments where time-dependent phenomena are examined was mentioned in Chapter 1. Many methods for investigating rapid events in biological systems, such as the use of fluorescent probes, yield little structural information. Examples of experiments with photoactivatable reagents that do yield such information have appeared recently. They include the use of a hydrophobic reagent to monitor the interaction of cholera toxin with membranes... 

The synthesis of the two diastereoisomers of P -l-(2-nitrophenyl)ethyl adenosine S -lri-phosphate (91) has been achieved using resolved (R)- and (5)-l-(2-nilroidienyl)ethanol. The alcohols were converted to (R)- and (5)-l-(2-nitrophenyl)ethyl phosphates by phosphitylation with N,)V-diisopropyl-fi(s-(2-cyanoethyl)phosphoramidite (92) and subsequent oxidation with 3-chlorobenzoic acid. Each of the monophosphates was activated with carbonyidiimidazole and condensed with adenosine diphosphate to give the desired triphosphate. These ATP analogues can be used for the rapid release (by flash photolysis) of ATP in biological systems. The 8-azido-3 -0-anthraniloyl derivatives of 2 -dADP (93) and 2 -dATP (94) have been prepared in seven steps from 8-azido-2 -deoxyadenosine. These compounds are of interest as fluorescent and photoactivatable probes for the nucleotide binding site of kinases and cyclases. In particular, (94) was shown to be a competitive inhibitor of Bordetella pertussis adenylate cyclase and the observed K- (74 pM) was close to tiiat predicted from the K- value of 3 -0-anthraniloyl-2 -dATP. ... 

The diphosphate (175), and the corresponding triphosphate, have been prepared as fluorescent and photoactivatable analogues for probing nucleotide binding sites. An efficient one-pot procedure has been... 

Verkhusha, V. V. and Sorkin, A. (2005). Conversion of the monomeric red fluorescent protein into a photoactivatable probe. Chem. Biol. 12,... 

Recently, a Ser-caged, photoactivatable fluorescent peptide probe that monitors protein kinase C (PKC) activity was described [75]. As expected, the Ser-caged peptide failed to serve as an effective PKC substrate in vitro, but upon light-induced deprotection (300-400nm, A.max360nm, 90s), the serine became phosphorylated and enzyme activity was recorded as a convincing change in the fluorescent properties of the probe. Photoconversion was estimated to occur with 60% yield and a quantum yield of 0.06. 

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