You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-(diethoxyphosphorylmethyl)-4-oxo-5H-[1,2,4]triazolo[4,3-a]quinoxaline-7-carbonitrile into its molecular formula.
user
C15H16N5O4P
assistant