3.1. Synthesis of NO photodonors Different mechanisms of NO release were reported, including intramolecular charge transfer (ICT) , photoinduced electron transfer (PET) , or homolythic fission with the formation of aminium radicals . BODIPY-based N-NO photodonors reported previously contain extended linker connecting BODIPY and NO-releasing moiety. On the other hand, N-NO group in several cases was directly attached to a chromophore . We decided to use short methylene linkage between BODIPY and N-NO. Such compounds are easily available starting from meso-CH2Cl-BODIPY 1a (Scheme 1). Substitution of Cl with I followed with reaction with primary amine (i-propylamine or aniline, respectively) gives amines 2a,b, whose nitrosation leads to N-nitroso donors BODIPY-NOD-1 and BODIPY-NOD-2.