You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2H-benzotriazol-5-yl-[(2R)-2-[6-[(dimethylamino)methyl]pyrazin-2-yl]pyrrolidin-1-yl]methanone into molecular formula.
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C18H21N7O
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