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What is the molecular formula of the molecule identified by tert-butyl N-(5b,8,8,11a-tetramethyl-2,9-dioxo-1-propan-2-yl-4,5,5a,6,7,7a,10,11,11b,12,13,13a-dodecahydro-3H-cyclopenta[a]chrysen-3a-yl)carbamate ?
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C33H51NO4
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