You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-[(4S,5R)-9-(benzenesulfonyl)-5-(dimethylamino)-9-azatricyclo[6.3.0.03,6]undeca-1,3(6),7,10-tetraen-4-yl]ethanol by IUPAC nomenclature, provide its molecular formula.
user
C20H22N2O3S
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