You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2R)-2-(1,4-dimethylimidazol-2-yl)pyrrolidin-1-yl]-(2,4-dimethyl-1,3-thiazol-5-yl)methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H20N4OS
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