5-((3aR,6S,6aS)-2-(4-((3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl)butyl)-3a,4,6,6a-tetrahydro-1H-thieno[3,4-d]imidazol-6-yl)pentanoic acid