5-(4-Fluoro-benzyl-idene)-4'-(4-fluoro-phen-yl)-1,1'-dimethyl-dispiro-[piperidine-3,3'-pyrrolidine-2',3''-indoline]-4,2''-dione

5-(4-Fluoro-benzyl-idene)-4'-(4-fluoro-phen-yl)-1,1'-dimethyl-dispiro-[piperidine-3,3'-pyrrolidine-2',3''-indoline]-4,2''-dione