You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 3-[5-chloro-4-oxo-2-[1-(7H-purin-6-yl)pyrrolidin-2-yl]quinazolin-3-yl]pyrrolidine-1-carboxylic acid into its molecular formula.
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C22H21ClN8O3
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