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system
Provide the molecular formula for the IUPAC named substance (13R)-4-amino-13-(2,5-dimethoxyphenyl)-6-methyl-11-oxo-8-thia-3,10-diazatricyclo[7.4.0.02,7]trideca-1(9),2(7),3,5-tetraene-5-carbonitrile .
user
C20H18N4O3S
assistant