Photoactivable fluorophores. 1. Synthesis and photoactivation ofo-nitrobenzyl-quenched fluorescent carbamates.

Abstract

The synthesis and photoactivation of a new type of fluorescent probe, the photoactivable fluorophore (PAF) are described. The PAFs described in this paper consist of fluorescent aromatic amines coupled to substituted nitrobenzyl quenching chromophores via a carbamate linkage. Photoactivation occurs by an intramolecular photo-redox reaction, converting the o-nitrobenzyl group to a labileo-nitrosobenzaldehyde hemiacetal which fragments with loss of CO2 to liberate the fluorescent amine. Photoactivation quantum yields also are reported.