You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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What is the molecular formula of the molecule identified by (4a-hydroxy-1,3,4,5,6,7,8,8a-octahydroisoquinolin-2-yl)-(6-bromopyridin-2-yl)methanone ?
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C15H19BrN2O2
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