You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4Z)-4-[(3-bromo-5-methoxy-4-propan-2-yloxyphenyl)methylidene]-2-(2-chloro-5-nitrophenyl)-1,3-oxazol-5-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H16BrClN2O6
assistant