You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Can you give the molecular formula of the molecule 5-[2-(2-amino-4-oxo-3,6,7,8-tetrahydropyrimido[5,4-b][1,4]thiazin-6-yl)ethyl]thiophene-2-carboxylic acid ?
user
C13H14N4O3S2
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