You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[3-[(6-methyl-1H-benzimidazol-2-yl)methyl]-1-(3-methylbutanoyl)piperidin-4-yl]acetic acid into molecular formula.
user
C21H29N3O3
assistant