4-[(4Z)-3-amino-4-[[1-(1-cyanoethyl)indol-3-yl]methylidene]-5-oxopyrazol-1-yl]benzoic acid;4-[3-amino-5-oxo-4-[(1-phenacylindol-3-yl)methylidene]pyrazol-1-yl]benzoic acid;4-[3-formyl-4-[[1-(1-methoxy-1-oxopropan-2-yl)indol-3-yl]methylidene]-5-oxopyrazol-1-yl]benzoic acid;2-[[4-[[1-(1-methoxy-1-oxopropan-2-yl)indol-3-yl]methylidene]-3-methyl-5-oxopyrazol-1-yl]methyl]benzoic acid;4-[3-methyl-5-oxo-4-[(1-propan-2-ylindol-3-yl)methylidene]pyrazol-1-yl]benzoic acid