You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule ethyl 2-[[2-(4-benzhydrylpiperazin-1-yl)acetyl]amino]-5-carbamoyl-4-methylthiophene-3-carboxylate into molecular formula.
user
C28H32N4O4S
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