(R)-tert-butyl 8-(3.5-difluorophenyl)-10-oxo-9-(2-oxo-2-((R)-2'-oxo-1.1'.2'.3-tetrahydrospiro[indene-2.3'-pyrrolo[2.3-b]pyridine]-5-ylamino)ethyl)-6.9-diazaspiro[4.5]decane-6-carboxylate