Water-soluble o-hydroxycinnamate as an efficient photoremovable protecting group of alcohols with fluorescence reporting

Two new o-hydroxycinnamates have been prepared for photoremovable protecting groups, and their photochemistry has been investigated. The photolysis of two caged compounds can efficiently release the corresponding alcohol in aqueous solutions, and the uncaging reaction proceeds with large one-photon excitation cross sections (1919 and 1535 M-1 cm(-1)). The uncaging process has been observed by NMR spectroscopy. The caged compounds exhibit good aqueous solubility and excellent resistance to hydrolysis in a buffer solution.