You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[4-[2-(4-amino-2-hydroxyanilino)-2-oxoethyl]-4-methylpiperazin-4-ium-1-yl]-N-(4-amino-2-hydroxyphenyl)acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H29N6O4+
assistant