You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2R,3S,4S,5R,6R)-6-[(2S,3S,4S,5R)-3,4-dihydroxy-2,5-bis(hydroxymethyl)oxolan-2-yl]oxy-3,4,5-trihydroxyoxan-2-yl]methyl 2,2,4-trimethyl-3-oxopentanoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H34O13
assistant