4(S)-<1(S)-<(tert-butyloxycarbonyl)amino>-3-methylbutyl>-3,3-difluoro-1-(methoxyphenyl)-2-azetidinone

N-(4-methoxyphenyl)-4(S)-<(tert-butyloxycarbonyl)amino>-2,2-difluoro-3(R)-hydroxy-6-methylheptanamide

sodium 4(S)-<(tert-butyloxycarbonyl)amino>-2,2-difluoro-3(R)-hydroxy-6-methylheptanoate

[(S)-1-((R)-2,2-Difluoro-1-(4-methoxy-phenylamino)-2-{(S)-2-methyl-1-[(pyridin-2-ylmethyl)-carbamoyl]-butylcarbamoyl}-ethyl)-3-methyl-butyl]-carbamic acid tert-butyl ester