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What is the molecular formula of the molecule 9-[(2R,4S,5R)-4-hydroxy-5-(hydroxymethyl)oxolan-2-yl]-2-[[(2R,3S)-2-hydroxy-3-pentacyclo[12.3.1.04,17.07,16.010,15]octadeca-1(18),4(17),5,7(16),8,10(15),11,13-octaenyl]amino]-1H-purin-6-one ?
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C28H23N5O5
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