Synthesis of azide-fluoro-dehydrocoelenterazine analog as a photoaffinity-labeling probe and photolysis of azide-fluoro-coelenterazine

A photosensitive azide-fluoro-dehydrocoelenterazine analog (Az-F-DCT) was synthesized, starting from 4-fluorophenylacetic acid, as a photoaffinity-labeling probe in order to analyze symplectin active site. To examine the photo-reactivity of Az-F-DCT, azide-fluoro-coelenterazine analog (Az-F-CT) was used as a potent symplectin chromophore model. Photolysis of Az-F-CT in 2,2,2-trifluoroethanol afforded nitrene intermediate to give an insertion product. The structure of this product was confirmed through spectroscopic analyses particularly by using a proton/deuterium (H/D) exchange experiments with ESI-Q-TOF-MS and -MS/MS measurement.