1 MGR Malachite green 1.000 2 1OM 4-{bis[4-(dimethylamino)phenyl]methyl}phenol 0.962 3 CVI Crystal violet 0.893 4 6FE 4-[[4-(dimethylamino)cyclohexa-2,5-dien-1-ylidene]-(4-methoxyphenyl)methyl]-N,N-dimethyl-aniline 0.733 5 AU4 4,4'-(aminomethylene)bis(N,N-dimethylaniline) 0.731