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system
Please write the molecular formula of the molecule 2-N,7-N,7-N'-tris[(2S)-3-methoxybutan-2-yl]-2-N'-[(3S)-3-methoxybutan-2-yl]-2-N,2-N',7-N,7-N'-tetrakis(4-methoxyphenyl)-9,9'-spirobi[fluorene]-2,2',7,7'-tetramine .
user
C73H84N4O8
assistant