You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (3S,10R,10aS)-10-methyl-3-(2-methylpropyl)-2,3,10,10a-tetrahydro-[1,3]thiazolo[3,2-b]isoquinolin-5-one into molecular formula.
user
C16H21NOS
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