You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3-[(5-chloro-8-hydroxy-3-methyl-1-oxo-3,4-dihydroisochromene-7-carbonyl)amino]-3-phenylpropanoic acid into molecular formula.
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C20H18ClNO6
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