You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance N-[2-[[1-[2-(diethylamino)ethyl]benzimidazol-2-yl]amino]-2-oxoethyl]thiophene-2-carboxamide .
user
C20H25N5O2S
assistant