You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2R)-2-[[(2S,3S)-3-methyl-2-[(3-oxo-2,4-dihydroquinoxaline-1-carbonyl)amino]pentanoyl]amino]-2-phenylacetic acid into its molecular formula.
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C23H26N4O5
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