You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 3-butan-2-yl-4-[2-(3-methyl-1,2,4-oxadiazol-5-yl)pyrrolidine-1-carbonyl]-3,5-dihydro-1H-1,4-benzodiazepin-2-one ?
user
C21H27N5O3
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