You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [(2S)-1-[4-[2-[6-amino-8-(2-bromo-4,5-dihydroxyphenyl)sulfanylpurin-9-yl]ethyl]piperidin-1-yl]-1-oxopropan-2-yl] 3-morpholin-4-ylpropanoate by IUPAC nomenclature, provide its molecular formula.
user
C28H36BrN7O6S
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