You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
9-[6'-(3-isocyanocarbazol-9-yl)spiro[3,13-diazatricyclo[7.4.0.02,7]trideca-1(9),2(7),3,5,10,12-hexaene-8,9'-thioxanthene]-3'-yl]carbazole-3-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C49H26N6S
assistant