You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-[6-[acetyl-[[(2S)-4-[(3,4-dichlorophenyl)methyl]morpholin-2-yl]methyl]amino]sulfanylpyrazin-2-yl]acetic acid into its molecular formula.
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C20H22Cl2N4O4S
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