You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named methyl (4R)-4-[(3R,8R,9S,10S,12S,13R,14S,17R)-3-ethoxycarbonyloxy-12-hydroxy-10,13-dimethyl-7-oxo-1,2,3,4,5,6,8,9,11,12,14,15,16,17-tetradecahydrocyclopenta[a]phenanthren-17-yl]pentanoate is given. What is its corresponding molecular formula?
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C28H44O7
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