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What is the molecular formula of the molecule (1S,2R,5S,6S,7R,8S,11R,17S,18R)-15-(chloromethyl)-18-[(3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy-5-ethyl-6,7-dihydroxy-2,6,8,11,13,17-hexamethyl-4,14,16-trioxa-9-azabicyclo[11.3.2]octadecan-3-one ?
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C31H57ClN2O9
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