You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-methyl-1-[1-(3-nitrophenyl)ethyl]-3-[3-(1,3-thiazol-4-ylmethoxy)phenyl]urea by IUPAC nomenclature, provide its molecular formula.
user
C20H20N4O4S
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