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 6-[(2-chloro-3,4-dimethoxyphenyl)methyl]-2-(2,3,4,5-tetrahydropyridin-6-yl)-3,5,7,8-tetrahydropyrido[4,3-d]pyrimidin-4-one into molecular formula.
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C21H25ClN4O3
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