You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 1-[3-(2-carbazol-9-ylpyridin-3-yl)pyridin-2-yl]-[1]benzothiolo[2,3-c]pyridine .
user
C33H20N4S
assistant