Comparative study of polyaromatic and polyheteroaromatic fluorescent photocleavable protecting groups

Fluorescent conjugates of N-benzyloxycarbonyl protected γ-aminobutyric acid were prepared by coupling to its C-terminus several polyheteroaromatic, based on the oxobenzopyran skeleton (trivially known as coumarin) and polyaromatic labels, such as naphthalene and pyrene. Photophysical properties were evaluated, as well as their behaviour towards photocleavage by irradiation in MeOH/HEPES buffer solution (80:20), in a photochemical reactor at different wavelengths (254, 300, 350 and 419 nm), followed by HPLC/UV monitoring.