You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(4-amino-7-benzyl-5,6-diphenylpyrrolo[2,3-d]pyrimidin-3-ium-3-yl)propan-1-ol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C28H27N4O+
assistant