2,5,6,10,13-Pentaazatetradecanedioic acid, 3,12-bis(1,1-dimethylethyl)-8-hydroxy-4,11-dioxo-9-(phenylmethyl)-6-[[4-(2-pyridinyl)phenyl]methyl]-, 1,14-dimethyl ester, (3S,8S,9R,12S)-; methyl ((5S,8R,9S,14S)-8-benzyl-5-(tert-butyl)-9-hydroxy-15,15-dimethyl-3,6,13-trioxo-11-(4-(pyridin-2-yl)benzyl)-2-oxa-4,7,11,12-tetraazahexadecan-14-yl)carbamate; 1,14-Dimethyl (3S,8S,9R,12S)-3,12-bis(1,1-dimethylethyl)-8-hydroxy-4,11-dioxo-9-(phenylmethyl)-6-[[4-(2-pyridinyl)phenyl]methyl]-2,5,6,10,13-pentaazatetradecanedioate;