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system
Can you give the molecular formula of the molecule 9-[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]-2-[[(1R)-7-(hydroxymethyl)-2,3-dihydro-1H-pyrrolizin-1-yl]amino]-1H-purin-6-one ?
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C18H22N6O6
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