You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2R,3R,4S,5S,6R)-3-[3-(butylamino)-2-hydroxypropoxy]-6-(hydroxymethyl)oxane-2,4,5-triol is the IUPAC name of a molecule. Please give its molecular formula.
user
C13H27NO7
assistant