You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (6R)-6-(5-bromothiophen-2-yl)-3-methylsulfanyl-7-propanoyl-2,6-dihydro-[1,2,4]triazino[1,6-c]quinazolin-5-ium-1-one into its molecular formula.
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C18H16BrN4O2S2+
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