1,3-Benzenedicarboxamide,N,N'-bis[4-[[2-hydroxy-3-[[(4-nitrophenyl)amino]carbonyl]-1-naphthalenyl]azo]phenyl]-N,N'-bis[[4-[[2-hydroxy-3-[[(4-nitrophenyl)amino]carbonyl]-1-naphthalenyl]azo]phenyl]methyl]-