Caged compounds with a steroid skeleton: synthesis, liposome-formation and photolysis

The synthesis of two key precursors for caging bioactive compounds, an o -nitrobenzyl p -nitrophenyl carbonate and an o -nitrobenzyl diazo compound with a steroid skeleton, is reported. The former is a suitable caging group for an amino group, while the latter is appropriate for a carboxylic acid. The resulting caged compounds were irradiated at 350 nm to afford the corresponding amine and carboxylic acid. A caged compound released bioactive compounds more efficiently when embedded in liposome than when in methanol.