methyl (4R,7S)-7-tert-butoxycarbonylamino-12,14-bis[(tert-butyl)dimethylsilyloxy]-1,3,4,5,6,7,8,10-octahydro-11-methyl-6,10-dioxo-9,2,5-benzoxathiaazacyclododecine-4-carboxylate

3,5-Bis-(tert-butyl-dimethyl-silanyloxy)-2-[(R)-2-methoxycarbonyl-2-(3-trityloxy-propionylamino)-ethylsulfanylmethyl]-6-methyl-benzoic acid 4-nitro-benzyl ester

2-[(R)-2-((S)-2-tert-Butoxycarbonylamino-3-hydroxy-propionylamino)-2-methoxycarbonyl-ethylsulfanylmethyl]-3,5-bis-(tert-butyl-dimethyl-silanyloxy)-6-methyl-benzoic acid 4-nitro-benzyl ester

(8R,11S)-11-Amino-2,4-bis-(tert-butyl-dimethyl-silanyloxy)-1-methyl-10,14-dioxo-5,7,8,9,10,11,12,14-octahydro-13-oxa-6-thia-9-aza-benzocyclododecene-8-carboxylic acid methyl ester

(8R,11S)-11-[((2S,3R)-1-tert-Butoxycarbonyl-3-hydroxy-pyrrolidine-2-carbonyl)-amino]-2,4-bis-(tert-butyl-dimethyl-silanyloxy)-1-methyl-10,14-dioxo-5,7,8,9,10,11,12,14-octahydro-13-oxa-6-thia-9-aza-benzocyclododecene-8-carboxylic acid methyl ester