You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 5-[2-[[5-(furan-2-ylmethylamino)-1,3,4-thiadiazol-2-yl]sulfanyl]propanoyl]-2,4-dimethyl-1H-pyrrole-3-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H20N4O4S2
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