You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6S,6aS)-3-[[3-[[(6S,6aS)-5-[[4-[[(2S)-2-[[(2S)-2-[3-(2,5-dioxopyrrol-1-yl)propanoylamino]-3-methylbutanoyl]amino]propanoyl]amino]phenyl]methoxycarbonyl]-6-hydroxy-2-methoxy-8-methylidene-11-oxo-6,6a,7,9-tetrahydropyrrolo[2,1-c][1,4]benzodiazepin-3-yl]oxymethyl]-5-[(2-methylpropan-2-yl)oxycarbonyl]phenyl]methoxy]-2-methoxy-8-methylidene-6-(oxan-2-yloxy)-11-oxo-6,6a,7,9-tetrahydropyrrolo[2,1-c][1,4]benzodiazepine-5-carboxylic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C70H80N8O20
assistant