You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-(1,2-benzoxazol-3-yl)-1-[4-(imidazol-1-ylmethyl)piperidin-1-yl]ethanone by IUPAC nomenclature, provide its molecular formula.
user
C18H20N4O2
assistant