You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [3-[(dimethylamino)methyl]-7-methyl-3,5-dihydro-2H-1,4-benzoxazepin-4-yl]-(5-methylpyrazin-2-yl)methanone;hydrochloride by IUPAC nomenclature, provide its molecular formula.
user
C19H25ClN4O2
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