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What is the molecular formula of the molecule 15,30-dimethyl-5,12,20,27-tetraoxo-2,17-diazaheptacyclo[16.12.0.03,16.04,13.06,11.019,28.021,26]triaconta-1(30),3,6,8,10,13,15,18,21,23,25,28-dodecaene-14,29-disulfonate ?
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C30H16N2O10S2-2
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