1 CYF 5-[2-(2-amino-2-carbamoyl-ethylsulfanyl)-acetylamino]-2-(3,6-dihydroxy-9,9a-dihydro-3h-xanthen-9-yl)-benzoic acid 1.000 2 52M 2-(6-hydroxy-3-oxo-3h-xanthen-9-yl)-5-[(sulfanylcarbonyl)amino]benzoic acid 0.757 3 6B9 2-(6-hydroxy-3-oxo-3h-xanthen-9-yl)-5-[(E)-(sulfanylmethylidene)amino]benzoic acid 0.730