You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (4S,11R,12R,21S)-9,17-dibutoxy-11,12,15-trihydroxy-19-methoxy-1',5'-dimethylspiro[7-oxa-8-azahexacyclo[14.6.1.02,14.04,12.06,10.020,23]tricosa-1(23),2(14),6(10),8,15,17,19-heptaene-21,6'-cyclohexene]-3,13-dione by IUPAC nomenclature, provide its molecular formula.
user
C37H43NO9
assistant