You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the compound with this IUPAC name 4-chloro-N-[2-(diethylamino)ethyl]-3-methyl-1-(4-methylphenyl)pyrazolo[3,4-b]pyridine-5-carboxamide ?
user
C21H26ClN5O
assistant