You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (2R,6S)-7-[(2-methyl-1,3-thiazol-4-yl)methyl]-4-[(5-methylthiophen-2-yl)methyl]-1,4,7-triazatricyclo[7.3.0.02,6]dodeca-9,11-dien-8-one by IUPAC nomenclature, provide its molecular formula.
user
C20H22N4OS2
assistant