You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (3R)-N-[(1R,2R,3R)-2,3-dimethylcyclohexyl]-3-methyl-1-oxo-2-(3-propan-2-yloxypropyl)-4H-pyrazino[1,2-a]benzimidazole-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C26H38N4O3
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