You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2S,3R,4S,5S,6R)-2-[(3S)-3,7-dimethylocta-1,6-dien-3-yl]oxy-4,5-dihydroxy-6-(hydroxymethyl)oxan-3-yl] acetate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H30O7
assistant