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-[(2R,4R,6S)-2-(4-chlorophenyl)-6-pyrazolo[1,5-a]pyrimidin-3-yloxan-4-yl]acetamide into molecular formula.
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C19H19ClN4O2
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