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 N-[4-[[6-(2-chlorophenyl)-8-methyl-7-oxopyrido[2,3-d]pyrimidin-2-yl]amino]cyclohexyl]methanesulfonamide into molecular formula.
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C21H24ClN5O3S
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