1,1'-((1,1'-Biphenyl)-4,4'-diylbis(2-oxo-2,1-ethanediyl))bis(1-methylpyrrolidinium 2Br) 123489-64-5 4,4'-Bis(pyrrolidinoacetyl)biphenyl dimethiobromide Pyrrolidinium, 1,1'-((1,1'-biphenyl)-4,4'-diylbis(2-oxo-2,1-ethanediyl))bis(1-methyl-, dibromide