You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2R)-3-methyl-N-(2-morpholin-4-ylethyl)-2-(4-oxo-1,2,3-benzotriazin-3-yl)butanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H25N5O3
assistant