You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (3R)-N-cyclooctyl-3-methyl-1-oxo-2-[(2S)-2-phenylpropyl]-4H-pyrazino[1,2-a]benzimidazole-3-carboxamide into molecular formula.
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C29H36N4O2
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