You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[2-[(1-amino-3-imino-4-phenylbutylidene)amino]-6,7-dihydro-1,3-benzothiazol-6-yl]acetic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H20N4O2S
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