You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (3aS,6aR)-N-butyl-5,5-dioxo-N-(4-propan-2-ylphenyl)-3a,4,6,6a-tetrahydrothieno[3,4-d][1,3]thiazol-2-amine ?
user
C18H26N2O2S2
assistant