You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[2-(4-tert-butylphenyl)-5-methyl-1,3-oxazol-4-yl]-N-(2-cyanopropan-2-yl)acetamide into molecular formula.
user
C20H25N3O2
assistant