(2S)-N-[(2S,5S)-3,3-difluoro-5-[[(2S)-3-methyl-2-[(methyl-(pyridin-2-y lmethyl)carbamoyl)amino]butanoyl]amino]-4-oxo-1,6-diphenyl-hexan-2-yl] -3-methyl-2-[(methyl-(pyridin-2-ylmethyl)carbamoyl)amino]butanamide