You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(10-bromo-6-phenyl-6,7-dihydro-[1,2,4]triazino[5,6-d][3,1]benzoxazepin-3-yl)methanethiol is the IUPAC name of a molecule. Please give its molecular formula.
user
C17H13BrN4OS
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