You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule [(3aS,4R,6S,7R,7aS)-7-(4-bromobutoxy)-6-ethylsulfanyl-2,2-dimethyl-4,6,7,7a-tetrahydro-3aH-[1,3]dioxolo[4,5-c]pyran-4-yl]methoxy-tert-butyl-dimethylsilane .
user
C21H41BrO5SSi
assistant