You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 3-[8-(dimethylamino)-8-thiophen-2-yl-2-azaspiro[4.5]decan-2-yl]-2,2-dimethyl-3-oxopropanenitrile .
user
C20H29N3OS
assistant