You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-methylpropyl (2S,3R)-2-[[2-(1,5-dimethyl-6-oxopyridin-3-yl)-1-[(2R)-1-methoxypropan-2-yl]benzimidazol-5-yl]methylamino]-3-hydroxybutanoate by IUPAC nomenclature, provide its molecular formula.
user
C27H38N4O5
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