You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-6-(imidazo[1,2-a]pyrazin-3-ylmethyl)-N-methyl-N-(1,3-thiazol-2-ylmethyl)-6-azaspiro[2.5]octan-2-amine is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H24N6S
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