Design and Synthesis of Two-Photon Responsive Chromophores for Near-Infrared Light-Induced Uncaging Reactions

Near-infrared two-photon (TP)-induced photorelease (uncaging) of bioactive molecules such as drugs has attracted considerable attention because of its ability to elucidate mechanistic aspects of biological processes. This short review summarizes recent developments in the design and synthesis of TP-responsive chromophores. 1 Introduction 2 Molecular Design of TP-Responsive Organic Chromophores for ‘Caging & Uncaging’ 2.1 π-Conjugation 2.2 A Dipolar System 2.3 A Quadrupolar System 2.4 An Octupolar System 3 Recent Developments of TP Uncaging Reactions 3.1 4-Methoxy-7-nitroindolinyl Caged Auxins 3.2 Uncaging of GABA and Tryptophan Using TP-Induced Electron-Transfer Reactions 3.3 Effect of Position Isomery in Aminoquinoline-Derived Photolabile Protecting Groups (PPGs) 3.4 Cooperative Dyads for TP Uncaging 3.5 Caged Calcium with a Bis-styrylthiophene Backbone 3.6 Cloaked Caged Compounds 3.7 Three-Dimensional Control of DNA Hybridization by Orthogonal Two-Color TP Uncaging 3.8 TP-Induced Release of Diethyl Phosphate (DEP) and ATP 4 Our Contribution to TP Uncaging Reactions 5 Summary