Boron, [N-​[6-​[(2,​5-​dioxo-​1-​pyrrolidinyl)​oxy]​-​6-​oxohexyl]​-​2-​[4-​[5-​[[5-​(2-​thienyl)​-​2H-​pyrrol-​2-​ylidene-​κN]​methyl]​-​1H-​pyrrol-​2-​yl-​κN]​phenoxy]​acetamidato]​difluoro-​, (T-​4)​-