You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[1-(4-pyridin-2-ylpiperazin-1-yl)propan-2-yl]-8lambda4-thia-7,9-diazabicyclo[4.3.0]nona-1(6),2,4,7,8-pentaene-2-sulfonamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H22N6O2S2
assistant