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What is the molecular formula of the molecule identified by [(2R,4R,4aR,4bR,8aS,10R,10aR)-6,10-diacetyloxy-2-ethenyl-10a-hydroxy-2,4b,8,8-tetramethyl-1,7-dioxo-3,4,4a,8a,9,10-hexahydrophenanthren-4-yl] benzoate ?
user
C31H36O9
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