You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-6-[(2S,3R)-3-[(3R)-6,8-dihydroxy-5-methyl-1-oxo-3,4-dihydroisochromen-3-yl]-2-hydroxybutyl]-4-hydroxy-5,5-dimethyloxane-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H31NO8
assistant