Abstract: Quinolone derivatives were recently reported for the first time by us for the protection of carboxylic acids, in the form of ester conjugates, by using an amino acid as model biomolecule. This nitrogen heterocycle, structurally related to coumarin, a well-known photocleavable protecting group 2-4 assured fast cleavage of the ester bond between the amino acid and the heterocycle. In this study a novel benzoquinolone was conjugated with two model amino acids and the photocleavage studies of the ester conjugates in different mixtures of methanol/HEPES buffer solution at different wavelengths of irradiation (300, 350 and 419 nm) confirmed the quantitative release of the model molecules in short irradiation times.   Acknowledgements: We thank the Fundação para a Ciência e Tecnologia (FCT) for financial support to the NMR portuguese network (PTNMR, Bruker Avance III 400-Univ. Minho), FCT and FEDER-COMPETE-QREN-EU for financial support to the Research Centre CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER-037302)], and a PhD grant to A.M.S.S. (SFRH/BD/80813/2011).