You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-[3-[(2R)-2,3-dimethyl-2H-imidazol-1-yl]-5-isocyano-2-methylphenyl]-3-methylisoquinolin-2-ium by IUPAC nomenclature, provide its molecular formula.
user
C23H23N4+
assistant