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 (4-ethylphenyl) 1-(4-butoxyphenyl)-6-chloro-1,3,4,9-tetrahydropyrido[3,4-b]indole-2-carboxylate into molecular formula.
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C30H31ClN2O3
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