You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule (9aR)-1'-(1-methylpiperidin-4-yl)-8-methylsulfonylspiro[1,3,4,7,9,9a-hexahydropyrazino[2,1-c][1,4]oxazine-6,3'-azetidine] into molecular formula.
user
C16H30N4O3S
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