You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule N-[(1E)-1-[(2E)-6-(4-chloroanilino)-2-ethylidenepyridin-3-ylidene]ethyl]-N',N'-diethylethane-1,2-diamine ?
user
C21H29ClN4
assistant