Azobenzenes in a new light-switching in vivo

Two bands make light work: since the isomerization of azobenzenes is usually induced by UV light, its application is limited in living systems. A new azobenzene switch now operates entirely in the visible range. The new design is based on the introduction of OMe groups in the ortho positions, which splits the n-π* transition into two absorption bands. The two isomeric forms can be obtained with more than 80 % enrichment from the respective photostationary state.