You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-[(4-methylphenyl)sulfonylamino]ethyl]-3-(3-thiophen-2-yl-1,2,4-oxadiazol-5-yl)propanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H20N4O4S2
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