Synonyms: H-BENZ[E]INDOLIUM, 2-[3-CHLORO-5-(1,3-DIHYDRO-1,1,3-TRIMETHYL-2H-BENZ[E]INDOL-2-YLIDENE)-1,3-PENTADIENYL]-1,1,3-TRIMETHYL-, PERCHLORATE;2-[(1E,3Z)-3-CHLORO-5-(1,1,3-TRIMETHYL-1,3-DIHYDRO-2H-BENZO[E]INDOL-2-YLIDENE)-1,3-PENTADIENYL]-1,1,3-TRIMETHYL-1H-BENZO[E]INDOLIUM PERCHLORATE;PK 680;2-[(1E,3Z)-3-Chloro-5-(1,1,3-trimethyl-1,3-dihydro-2H-benzo[e]indol-2-ylidene)-1,3-pentadienyl]-1,1,3-trimethyl-1H-benzo[e]indolium perchlorate