You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3,5-dimethoxyphenyl)-[4-(9-methoxybenzo[b][1,4]benzoxazepin-6-yl)-2-methylpiperazin-1-yl]methanone by IUPAC nomenclature, provide its molecular formula.
user
C28H29N3O5
assistant