You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2R)-2-[4-(4-methoxyphenyl)piperazin-1-yl]-2-(2-phenyl-1H-indol-3-yl)acetic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C27H27N3O3
assistant