You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-cyclohexyl-N-ethyl-2-[(2-methyl-[1,2,4]triazolo[1,5-c]quinazolin-5-yl)sulfanyl]propanamide into its molecular formula.
user
C21H27N5OS
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