You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 2-amino-5-[(9S)-6-morpholin-4-yl-11-oxa-1,3,5-triazatricyclo[7.4.0.02,7]trideca-2,4,6-trien-4-yl]pyrimidine-4-carbonitrile into molecular formula.
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C18H20N8O2
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