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 methyl 2-[(9S)-5-benzyl-4,13-dimethyl-3-thia-1,8,11,12-tetrazatricyclo[8.3.0.02,6]trideca-2(6),4,10,12-tetraen-9-yl]acetate .
user
C20H22N4O2S
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