You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2S,3R,4S)-2-[8-[2-(3-fluorophenyl)ethylamino]imidazo[1,2-a]pyrazin-3-yl]thiolane-3,4-diol into its molecular formula.
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C18H19FN4O2S
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