(-)-(3S,9S,14aR)-9-benzyl-3-[(S)-7-hydroxy-6-oxooctyl]-6,6-dimethyldecahydropyrrolo[1,2-a][1,4,7,10]tetraazacyclododecine-1,4,7,10-tetraone

(-)-ethyl 8-[(3S,9S,14aR)-9-benzyl-6,6-dimethyl-1,4,7,10-tetraoxotetradecahydropyrrolo[1,2-a][1,4,7,10]tetra-azacyclododecin-3-yl]-3-oxooctanoate

(3S,9S,14aR)-9-benzyl-3-(7-bromo-6-oxoheptyl)-6,6-dimethyldecahydropyrrolo[1,2-a][1,4,7,10]tetraazacyclododecine-1,4,7,10-tetraone

S-7-((3S,9S,14aR)-9-benzyl-6,6-dimethyl-1,4,7,10-tetraoxotetradecahydropyrrolo[1,2-a][1,4,7,10]tetraazacyclododecin-3-yl)-2-oxoheptyl O-ethyl carbonodithioate

benzyl 6-[(3S,9S,14aR)-9-benzyl-6,6-dimethyl-1,4,7,10-tetraoxotetradecahydropyrrolo[1,2-a][1,4,7,10]tetraazacyclododecin-3-yl]-4-(ethoxycarbonothioylthio)hexanoate