You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3R,4S,5S,6R)-1-[(2R,3S,4R,5R)-4,5-dihydroxy-2-(hydroxymethyl)-6-[(2R,3S,4R,5R,6S)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxan-3-yl]oxy-3-(hydroxymethyl)-2-oxa-7-selenabicyclo[4.1.0]heptane-4,5,6-triol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H30O16Se
assistant