You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2R)-N-(1,3-benzodioxol-5-yl)-2-[(5-methyl-[1,2,4]triazolo[4,3-a]quinolin-1-yl)sulfanyl]propanamide into its molecular formula.
user
C21H18N4O3S
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