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system
Provide the molecular formula for the IUPAC named substance (6R,8R,8aS)-8-methyl-2-(4-methylphenyl)-6-[(1S,2S,4S,5'R,6R,7S,8R,9S,12S,13R,16S)-5',7,9,13-tetramethylspiro[5-oxapentacyclo[10.8.0.02,9.04,8.013,18]icos-18-ene-6,2'-oxane]-16-yl]oxy-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxin-7-ol;(6R,8R,8aS)-2-(4-methylphenyl)-6-[(1S,2S,4S,5'R,6R,7S,8R,9S,12S,13R,16S)-5',7,9,13-tetramethylspiro[5-oxapentacyclo[10.8.0.02,9.04,8.013,18]icos-18-ene-6,2'-oxane]-16-yl]oxy-4,4a,6,7,8,8a-hexahydropyrano[3,2-d][1,3]dioxine-7,8-diol;1-phenylethanone .
user
C91H126O16
assistant