[8-[[4-[4-[[3-(4-chlorobenzoyl)oxy-8-methyl-8-azoniabicyclo[3.2.1]octan-8-yl]methyl]phenyl]phenyl]methyl]-8-methyl-8-azoniabicyclo[3.2.1]octan-3-yl] 4-chlorobenzoate;dibromide