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system
Provide the molecular formula for the IUPAC named substance (2R)-2-amino-3-[[3-cyano-1-(3,4-dichlorophenyl)-5-hydroxy-2-imino-7a-methyl-6,7-dihydroindol-7-yl]sulfanyl]propanoic acid .
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C19H18Cl2N4O3S
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