You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4Z)-3-[4-[2-[(Z)-[2-benzylsulfanyl-3-[(1,3-diethylbenzimidazol-2-ylidene)methyl]-4-oxocyclobut-2-en-1-ylidene]methyl]-1,3-benzoxazol-3-ium-3-yl]butylsulfanyl]-2-[(Z)-[1-ethyl-3-(2-hydroxyethyl)benzimidazol-2-ylidene]methyl]-4-[[3-(2-hydroxyethyl)-1,3-benzoxazol-3-ium-2-yl]methylidene]cyclobut-2-en-1-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C61H60N6O6S2+2
assistant