You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 4-[[(28S)-28-ethylpentacyclo[20.5.1.12,7.18,14.015,21]triacontane-4-carbonyl]amino]butanoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C38H65NO3
assistant