rac-(2'S,3'R,4'S,5'R)-6-chloro-4'-(3-chloro-2-fluoro-phenyl)-2'-(2,2-dimethyl-propyl)-2-oxo-1,2-dihydro-spiro[indole-3,3'-pyrrolidine]-5'-carboxylic acid (2-oxo-1,2-dihydro-pyridin-4-yl)-amide