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What is the molecular formula of the molecule methyl 2-[(1S,7S,9R,12R)-7-methoxy-12-phenyl-8,11,13-trioxa-3,4-diazatricyclo[7.4.0.02,6]trideca-2,5-dien-4-yl]acetate ?
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C18H20N2O6
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