It is a mixture of the trisulfonates of triphenyl rosaniline and of diphenyl rosaniline. Great Lakes was a major producer of polybrominated diphenyl ethers. Resistance to acifluorfen and other diphenyl ether herbicides has been reported. Eleven products contained prohibited levels of lead, and one of polybrominated diphenyl ether flame retardants. In 2004 and 2008 the EU banned several types of polybrominated diphenyl ethers (PBDEs). The simplest members of these classes are dimethyl carbonate and diphenyl carbonate. Stanley's work contributed to on lepracidal compounds, diphenyl stereochemistry and the chemistry of the sterols. Polycarbonates can be prepared by transesterifying diphenyl carbonate with bisphenol A. Phenol is a co-product. Their chlorine analogs are polychlorinated diphenyl ethers (PCDEs). Since May 2009, this treaty also covers polybrominated diphenyl ethers and perfluorooctanesulfonic acid. Diphenyl carbonate is also prepared similarly, but using palladium catalysts. Benzil, (PhCO), is the corresponding diphenyl derivative. This facility has South Asia's first methylene diphenyl diisocyanate (MDI) splitter for processing crude MDI. Methylene diphenyl diisocyanate, most often abbreviated as MDI, is an aromatic diisocyanate. A well-known tetrazole is dimethyl thiazolyl diphenyl tetrazolium bromide (MTT).