You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl N-[3-[[[ethylamino-[(1-methyl-6-oxopiperidin-3-yl)amino]methylidene]amino]methyl]pentan-3-yl]carbamate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H39N5O3
assistant