You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-[1-(3,4-dichlorophenyl)ethyl]-4-isocyano-5-morpholin-4-ylthiophene-2-carboxylic acid by IUPAC nomenclature, provide its molecular formula.
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C18H16Cl2N2O3S
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