You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 5-chloro-4-[[(1S)-1-(2-chloro-5-fluorophenyl)ethyl]amino]-2-fluoro-N-pyrazin-2-ylbenzenesulfonamide into molecular formula.
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C18H14Cl2F2N4O2S
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