You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6R)-4-methyl-8-oxo-7-[[2-phenyl-2-(pyridine-4-carbonyloxy)acetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H19N3O6S
assistant