You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (4R,5S,6S)-3-[2-[4-(acetyloxymethyl)-1,3-thiazol-5-yl]ethenylsulfanyl]-6-[(1R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid .
user
C18H20N2O6S2
assistant