You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-N,1-N-diethyl-4-N-methyl-4-N-[2-(methylamino)ethyl]piperidine-1,4-dicarboxamide;hydrochloride is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H31ClN4O2
assistant