You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,2R,5S,7S,9R,10S,15R,16R)-15-[(E,2R,5R)-5,6-dimethylhept-3-en-2-yl]-5,10-dihydroxy-2,16-dimethyl-8-oxapentacyclo[9.7.0.02,7.07,9.012,16]octadec-11-en-13-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C28H42O4
assistant