5-((3aS,4S,6aR)-1-Nitroso-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl)pentanoic acid; 1H-Thieno[3,4-d]imidazole-4-pentanoic acid, hexahydro-1-nitroso-2-oxo-, [3aS-(3aα,4β,6aα)]; 1′-Nitrosobiotin