You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(4-hydrazinyl-5,6-dimethylthieno[2,3-d]pyrimidin-2-yl)methyl-(2-hydroxyethyl)amino]ethanol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C13H21N5O2S
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