(3E)-3-[5-(5-hydroxy-1H-indol-3-yl)-2-oxo-1H-pyrrol-3-ylidene]-1H-indol-2-one (3E)-3-[5-(5-hydroxy-1H-indol-3-yl)-2-oxo-1H-pyrrol-3-ylidene]indolin-2-one (3E)-3-[5-(5-hydroxy-1H-indol-3-yl)-2-oxo-1H-pyrrol-3-ylidene]-2-indolinone (3E)-3-[5-(5-hydroxy-1H-indol-3-yl)-2-keto-2-pyrrolin-3-ylidene]oxindole NChemBio.2007.20-comp21