Nucleobase-caged phosphoramidites for oligonucleotide synthesis.

Caged compounds are biologically active agents bearing a photolabile group in a strategic position, which makes them temporarily inactive. These compounds can then be delivered to a biological sample without immediately generating an effect. When the sample is then irradiated, e.g., with a laser in a (confocal) microscope, the activity of the substance is released with exact spatiotemporal and dose control. This unit deals with the synthesis of protected nucleoside phosphoramidites bearing a caging group on the nucleobase, which prevents the nucleobases from forming normal Watson-Crick base pairs. These amidites can be used to generate caged oligodeoxynucleotides with a transitory local perturbation that adds an element of spatiotemporal control to oligonucleotide-based applications.