You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7-[(2S)-2-hydroxypropyl]-6-methyl-2-[[(1S)-1-pyridin-3-ylethyl]amino]thieno[3,2-d]pyrimidine-4-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H21N5O2S
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