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What is the molecular formula of the compound with this IUPAC name 2-amino-9-[(2R,3R,4R,5R)-3,4-dihydroxy-5-(hydroxymethyl)-3-methyloxolan-2-yl]-1-(1-oxo-1-phenylpropan-2-yl)purin-6-one ?
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C20H23N5O6
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