You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name ethyl 4-cyano-5-[[(E)-2-cyano-3-(2-propoxyphenyl)prop-2-enoyl]amino]-3-methylthiophene-2-carboxylate into its molecular formula.
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C22H21N3O4S
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