You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[(2,4-dimethylphenyl)carbamoyl]-2-[(5-phenyl-1,3,4-oxadiazol-2-yl)sulfanyl]propanamide into molecular formula.
user
C20H20N4O3S
assistant