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 (1R)-7-chloro-2-[(3R)-1,1-dioxothiolan-3-yl]-1-(4-methylphenyl)-1H-chromeno[2,3-c]pyrrole-3,9-dione into molecular formula.
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C22H18ClNO5S
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