You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named N-(cyclohexa-1,5-dien-1-ylmethyl)-N-methyl-2-phenyl-[1,2,4]triazolo[1,5-a]pyridine-7-carboxamide is given. What is its corresponding molecular formula?
user
C21H20N4O
assistant