You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6R)-7-[[(2E)-2-(2-amino-1,3-thiazol-4-yl)-2-ethoxyiminoacetyl]amino]-8-oxo-3-[(E)-2-pyridin-3-ylethenyl]-5-thia-1-azabicyclo[4.2.0]octane-3-carboxylic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H22N6O5S2
assistant