Complex sentence: Benzidine is the trivial name for 4,4'-diaminobiphenyl, a carcinogenic aromatic amine which has been used as part of a test for cyanide and also in the synthesis of dyes.
Split into simpler sentences: Benzidine is the trivial name for the organic compound 4,4'-diaminobiphenyl. This aromatic amine which has been used as part of a test for cyanide and also in the synthesis of dyes.