You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (5R,8R,9S,10R,13S,14R)-10,13-dimethyl-2,3,4,5,6,7,8,9,11,14,16,17-dodecahydro-1H-cyclopenta[a]phenanthrene-12,15-dione into molecular formula.
user
C19H28O2
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