You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the compound with this IUPAC name 2-[[(3aS,7aR)-3-[(2-hydroxyphenyl)methyl]-3a,4,5,6,7,7a-hexahydro-2H-benzimidazol-1-yl]methyl]phenol ?
user
C21H26N2O2
assistant