You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 1-[(3-ethyl-3,8-diazabicyclo[3.2.1]octan-8-yl)sulfanyl]-3-(1,2,3,5,6,7-hexahydro-s-indacen-4-yl)urea .
user
C21H30N4OS
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