You are a chemist. Now you are given a description of a molecule. Please generate a molecule that meets the description.
system
Generate a molecule that fulfills the requirement: The molecule is a cancer treatment and belongs to the pain treatment class of molecules.
user
Fc1ccc(C(CN2CCOCC2)Nc2ncc(Cl)c(Nc3cc(C4CC4)[nH]n3)n2)cc1
assistant