You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)-N-[(3S)-2,3-dihydro-1-benzofuran-3-yl]butanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H23N3O3
assistant