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What is the molecular formula of the molecule 21-[3-[10-(1,7,8,8a-tetrahydronaphthalen-2-yl)anthracen-9-yl]phenyl]-18,18-dimethyl-9-thiahexacyclo[15.7.0.02,10.03,8.011,16.019,24]tetracosa-1(17),2(10),3,5,7,11,13,15,19(24),20,22-undecaene ?
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C55H40S
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