You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule (6aR,9R,10aR)-7-methyl-N-(3-methyl-1,2-thiazol-5-yl)-6,6a,8,9,10,10a-hexahydro-4H-indolo[4,3-fg]quinoline-9-carboxamide ?
user
C20H22N4OS
assistant