You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1S,2S,3R,7S,11S,15S,18R,19R,20S)-2,11-dihydroxy-18-(1H-indol-3-ylmethyl)-1,7,9,20-tetramethyl-21-oxa-17-azatetracyclo[16.2.1.03,15.015,19]henicosa-4,8-diene-10,14,16-trione is the IUPAC name of a molecule. Please give its molecular formula.
user
C32H38N2O6
assistant