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What is the molecular formula of the molecule 5,5-dimethyl-15-piperazin-1-yl-6,17-dithia-2,12,14-triazatetracyclo[8.7.0.03,8.011,16]heptadeca-1(10),2,8,11(16),12,14-hexaene ?
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C18H21N5S2
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