You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-[1-[2-(4-chloroanilino)-2-oxoethyl]-2,4-dioxo-5,6,7,8-tetrahydro-[1]benzothiolo[2,3-d]pyrimidin-3-yl]acetic acid .
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C20H18ClN3O5S
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