You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-chloro-7-[(2S)-1-[[hydroxy-[(2-methylpropan-2-yl)oxy]methyl]amino]-3-methylpentan-2-yl]pyrrolo[2,3-d]pyrimidine-6-carboxylic acid .
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C18H27ClN4O4
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