You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2S)-2-[[(2S,3S)-3-methyl-2-(4-oxo-1,2,3-benzotriazin-3-yl)pentanoyl]amino]-4-methylsulfanylbutanoic acid by IUPAC nomenclature, provide its molecular formula.
user
C18H24N4O4S
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