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What is the molecular formula of the molecule [(4aS,4bR,8S,10aR,10bS,12aS)-10a,12a-dimethyl-6-nitro-3-oxo-1,4,4a,4b,5,7,8,9,10,10b,11,12-dodecahydronaphtho[2,1-f]isochromen-8-yl] acetate ?
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C21H29NO6
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