You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(5-phenylsulfanyl-9,15-diazatetracyclo[10.2.1.02,10.03,8]pentadeca-2(10),3(8),4,6-tetraen-9-yl)ethanol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22N2OS
assistant