You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(E)-(4-carboxypiperidin-1-yl)-[(2-methylpropan-2-yl)oxycarbonyloxymethoxyimino]-oxidoazanium The above is the IUPAC name of a molecule. Write its molecular formula.
user
C12H21N3O7
assistant