You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (6S,7S)-5-hydroxy-6-methoxy-2-phenyl-3a,4,5,6,7,7a-hexahydro-4,7-epoxyisoindole-1,3-dione ?
user
C15H15NO5
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