You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (3S)-3-[2-(4-ethylpiperazin-1-yl)-2-oxoethyl]-7-methyl-2,3-dihydro-[1,3]thiazolo[3,2-a]pyrimidin-5-one .
user
C15H22N4O2S
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