[{"from": "human", "value": "Could you provide a description of this molecule? [C][C][N][C][=C][Branch2][Ring1][=Branch2][C][=C][C][=C][Ring1][=Branch1][N][=C][Ring1][=Branch2][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][C][C][18F][C][=Branch1][C][=O][N][Ring2][Ring1][Branch2]"}, {"from": "gpt", "value": "The molecule is a radiotracer consisting of an analogue of the poly(ADP-ribose) polymerase 1 (PARP1) inhibitor rucaparib radiolabeled with the positron emitting isotope fluorine F 18, which can potentially be used for the imaging of PARP1 expression using positron emission tomography (PET). Upon administration, fluorine F 18 fluorthanatrace targets and binds to PARP1. Upon PET, PARP1-expressing tumor cells can be visualized. PARP1, which is overexpressed in many cancer cell types, catalyzes post-translational ADP-ribosylation of nuclear proteins and plays a key role in the repair of DNA strand breaks."}]