1-((S)-5-Amino-5-carboxy-pentyl)-3,4-bis-((S)-3-amino-3-carboxy-propyl)-1H-pyrrole-2-carboxylic acid benzyl ester

(-)-benzyl-3,4-bis[(3S)-3-[bis-(tert-butylcarbonyl)amino]-4-(tert-butoxy)-4-oxobutyl]-1-[(5S)-5-[bis(tert-butoxycarbonyl)amino]-6-(tert-butoxy)-6-oxohexyl]-1H-pyrrole-2-carboxylate