You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (4aS)-9-chloro-5',5'-dimethylspiro[2,4,4a,6-tetrahydro-1H-[1,4]thiazino[4,3-a]quinoline-5,2'-cyclohexane]-1',3'-dione ?
user
C19H22ClNO2S
assistant