27 Benzidine Benzidine is the organic compound with the formula (C6H4NH2)2. it is an aromatic amine. It is prepared in a two step process from nitrobenzene. First, the nitrobenzene is converted to 1,2-diphenylhydrazine, usually using iron powder as the reducing agent. Treatment of this hydrazine with mineral acids induces a rearrangement reaction to 4,4'-benzidine. Smaller amounts of other isomers are also formed. The benzidine rearrangement, which proceeds intramolecularly, is a classic mechanistic puzzle in organic chemistry. This aromatic amine is a component of a test for cyanide and also in the production of dyes. Benzidine has been linked to bladder and pancreatic cancer. Since August 2010 benzidine dyes are included in the EPA's List of Chemicals of Concern. 92-87-5 7111 C12H12N2 184.100050 White powder. 120°C 0.322 mg/mL at 25°C Oral (L95) ; inhalation (L95) ; dermal (L95) DNA (L95) N-acetylated benzidine metabolites are believed to form adducts with nucleic acids. Carcinogenesis is initiated when they are activated by peroxidation by prostaglandin H synthetase, oxidation by cytochrome P-450, or O-esterification by O-acetyltransferase or N,O-acetyltransferase. Benzidine has also been shown to bind to RNA and hemoglobin. (L95, A55) Benzidine is absorpted following inhalation, oral, and dermal routes of exposure. Metabolism involves multiple and complex enzymatic pathways, including cytochrome P-450 and flavin monooxygenase systems, peroxidation by prostaglandin H synthase, and oxidation by lipoxygenases. The main reactions involved are N-acetylation, N-oxidation, and N-glucuronidation. Benzidine and its metabolites are excreted in the urine and faeces. (L95) LD50: 309 mg/kg (Oral, Rat) (T14) LD50: 110 mg/kg (Intraperitoneal, Mouse) (T14) 1, carcinogenic to humans. (L135) Benzidine was used to produce dyes for cloth, paper, and leather. (L95) Benzidine is a known human carcinogen, most often associated with cancer of the urinary bladder. If benzidine comes in contact with skin it may cause a skin allergy. Liver, kidney, immune, and neurological effects have also been observed in animals exposed to benzidine. (L95) 2009-03-06T18:57:56Z 2014-12-24T20:20:55Z Prostaglandin G/H synthase 1 (P23219) Choline O-acetyltransferase (P28329) Carnitine O-acetyltransferase (P43155) Arylamine N-acetyltransferase 1 (P18440) Arylamine N-acetyltransferase 2 (P11245) Arachidonate 5-lipoxygenase (P09917) Arachidonate 12-lipoxygenase, 12S-type (P18054) Arachidonate 12-lipoxygenase, 12R type (O75342) Arachidonate 15-lipoxygenase (P16050) Arachidonate 15-lipoxygenase type II (O15296) Cytochrome P450 1A1 (P04798) Cytochrome P450 1A2 (P05177) (L95, A55, A56, A57) http://en.wikipedia.org/wiki/Benzidine C16444 C029876 Benzidine 139 true Prostaglandin G/H synthase 1 (P23219) Choline O-acetyltransferase (P28329) Carnitine O-acetyltransferase (P43155) Arylamine N-acetyltransferase 1 (P18440) Arylamine N-acetyltransferase 2 (P11245) Arachidonate 5-lipoxygenase (P09917) Arachidonate 12-lipoxygenase, 12S-type (P18054) Arachidonate 12-lipoxygenase, 12R type (O75342) Arachidonate 15-lipoxygenase (P16050) Arachidonate 15-lipoxygenase type II (O15296) Cytochrome P450 1A1 (P04798) Cytochrome P450 1A2 (P05177) (L95, A55, A56, A57) NC1=CC=C(C=C1)C1=CC=C(N)C=C1 C12H12N2 InChI=1S/C12H12N2/c13-11-5-1-9(2-6-11)10-3-7-12(14)8-4-10/h1-8H,13-14H2 InChIKey=HFACYLZERDEVSX-UHFFFAOYSA-N 184.2371 184.100048394 Exogenous Solid 1.34 HMDB41835 CHEMBL15901 6844