You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyoxan-2-yl]oxy-5,7-dihydroxy-2-(4-hydroxyphenyl)chromen-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C27H30O16
assistant