You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(9R)-9-ethyl-13-ethylsulfanyl-9-methyl-11-oxo-12,14,15,17-tetrazatetracyclo[8.7.0.02,7.012,16]heptadeca-1(10),2,4,6,13,16-hexaen-15-yl]-N-(4-methylphenyl)acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C27H29N5O2S
assistant