You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S,6R)-4-[(2-methoxypyridin-3-yl)methyl]-7-[(2-methyl-1,3-thiazol-4-yl)methyl]-1,4,7-triazatricyclo[7.3.0.02,6]dodeca-9,11-dien-8-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H23N5O2S
assistant