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What is the molecular formula of the compound with this IUPAC name 3-(1,3-benzothiazol-2-yl)-1-[2-[(1S)-1-hydroxyethyl]-6,7-dihydro-4H-pyrazolo[1,5-a]pyrazin-5-yl]propan-1-one ?
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C18H20N4O2S
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