DAB IS METABOLIZED VIA FOLLOWING PATHWAYS: 1) REDUCTION & CLEAVAGE OF AZO GROUP; 2) DEMETHYLATION; 3) RING HYDROXYLATION; 4) N-HYDROXYLATION; 5) N-ACETYLATION & O-CONJUGATION OF METABOLITES.
IN RATS & MICE, CARCINOGENIC AROMATIC AZO-DYES UNDERGO N-HYDROXYLATION, & FOR EXAMPLE, N-HYDROXY-N-ACETYL-4-AMINOAZOBENZENE IS URINARY METABOLITE OF HEPATOCARCINOGENIC 4-DIMETHYLAMINOAZOBENZENE ... .
A study was made of the azoreduction of dimethylaminoazobenzene (DAB) in-vitro by purified rat liver NADPH cytochrome p450-reductase and by a partially purified reconstituted cytochrome p450 system. Male Wistar rats were induced with clofibrate, nafenopin, phenobarbital, or beta-naphthoflavone prior to liver microsomal isolation. ... Both purified NADPH cytochrome p450 reductase and the reconstituted system reduced dimethylaminoazobenzene, with a more than five fold greater rate for the latter. A ratio of 2:1 azoreductase to cytochrome p450 was optimal for dimethylaminoazobenzene reduction. Clofibrate was the only inducer of azoreductase. Reaction with the suicide inhibitor 10-undecynoic acid distinguished laurate hydroxylase from the azoreductase. The reconstituted system was active in air and carbon monoxide, while purified NADPH cytochrome p450 reductase was inhibited in air. In both systems, nearly 50 fold acceleration of dimethylaminoazobenzene azoreduction occurred in the presence of flavin adenine dinucleotide or flavin mononucleotide, but only under anaerobic conditions, indicating facilitation of electron flow to dimethylaminoazobenzene onlhy from NADPH cytochrome p450-reductase and not from cytochrome p450 itself. This was confirmed with the use of cytochrome p450 inhibitors. ... There appears to be an obilgatory electron flow through cytochrome p450 to dimethylaminozaobenzene, bypassing an oxygen sensitive step, and dietary riboflavin probably attenuates dimethylaminoazobenzene hepatocarcinogenicity solely by its effect on intestinal bacteria.
The Human Health Assessment Group in EPA's Office of Health and Environmental Assessment has evaluated dimethylaminoazobenzene for carcinogenicity. According to their analysis, the weight-of-evidence for dimethylaminoazobenzene is group B2, which is based on no evidence in humans and sufficient evidence in animals. As a group B2 chemical, dimethylaminoazobenzene is considered to be probably carcinogenic to humans.
No data are available in humans. Sufficient evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 2B: The agent is possibly carcinogenic to humans.
MORE THAN HALF OF BOUND DYE IN ALL LIVER-CELL FRACTIONS IS ASSOC WITH SOL PROTEINS; OF THIS, 80% IS BOUND TO FRACTION WHICH ACCOUNTS FOR ONLY 15% OF SOL PROTEINS.
BILIARY EXCRETION OF THE AZO DYE CARCINOGEN, N,N-DIMETHYL-4-AMINOAZO(C-14)BENZENE (DAB) WAS STUDIED IN MALE RATS. AFTER A SINGLE IV DOSE OF CARCINOGEN, 20-25% OF THE INJECTED RADIOACTIVITY APPEARS IN THE BILE WITHIN 1 HR, ENTIRELY AS METABOLITES.
IT WAS ADMIN IP TO WISTAR RATS & FOUND TO HAVE THE TENDENCY TO BIND TO LIVER TISSUES, NUCLEI & CHROMATIN WITH SPECIFIC BINDING AFFINITY TO NUCLEAR NONHISTONE PROTEIN.
1.周国泰,化学危险品安全技术全书,化学工业出版社,1997 2.国家环保局有毒化学品管理办公室、北京化工研究院合编,化学品毒性法规环境数据手册,中国环境科学出版社.1992 3.Canadian Centre for Occupational Health and Safety,CHEMINFO Database.1998 4.Canadian Centre for Occupational Health and Safety, RTECS Database, 1989
A Convenient and General Ruthenium-Catalyzed Transfer Hydrogenation of Nitro- and Azobenzenes
作者:Rajenahally V. Jagadeesh、Gerrit Wienhöfer、Felix A. Westerhaus、Annette-Enrica Surkus、Henrik Junge、Kathrin Junge、Matthias Beller
DOI:10.1002/chem.201102276
日期:2011.12.16
An easily accessible in situ catalyst composed of [RuCl2(p‐cymene)}2] and terpyridine has been developed for the selective transferhydrogenation of aromatic nitro and azo compounds. The procedure is general and the selectivity of the catalyst has been demonstrated by applying a series of structurally diverse nitro and azo compounds (see scheme).
Nano-CuFe2O4-supported sulfonic acid as a novel and recyclable nanomagnetic acid for diazotization of aromatic amines: efficient synthesis of various azo dyes
作者:Firouzeh Nemati、Ali Elhampour、Mahshid B. Natanzi、Samaneh Sabaqian
DOI:10.1007/s13738-016-0818-x
日期:2016.6
magnetometer. Then the novel acidic reagent was examined in synthesis of various azo-containing compounds from coupling of aryl diazonium ferrite sulfate salts with aromatic and non-aromatic compounds. The procedure starts by diazotization of aromatic amines with NaNO2 and wet CuFe2O4–SO3H and then coupling reaction of aryl diazonium ferrite sulfate salts with appropriate reagent. The prepared nano-solid
NH<sub>4</sub>I/<i>tert</i>-Butyl Hydroperoxide-Promoted Oxidative C–N Cleavage of Tertiary Amines Leading to Nitroaromatic Compounds
作者:Ying Shao、Hao Zheng、Zhuhong Wu、Lei Huang、Jingjing Tong、Ming Wu、Xiaoqiang Sun
DOI:10.3184/174751917x15022797727991
日期:2017.9
A NH4I/tert-butyl hydroperoxide-promoted oxidation of tertiary N-aryl-N,N-dialkylamines in DMSO has been developed to access nitroaromatic compounds. This methodology involves sequential N-dealkylation reactions in one-pot and a radical pathway is proposed.
Cobalt‐Catalyzed Deoxygenative Hydroboration of Nitro Compounds and Applications to One‐Pot Synthesis of Aldimines and Amides
作者:Kristina A. Gudun、Raikhan Zakarina、Medet Segizbayev、Davit Hayrapetyan、Ainur Slamova、Andrey Y. Khalimon
DOI:10.1002/adsc.202101043
日期:2022.2
The commercially available and bench-stable Co(acac)2 ligated with bis[(2-diphenylphosphino)phenyl] ether (dpephos) was employed for selective room temperature hydroboration of nitro compounds with HBPin (TOF up to 4615 h−1), tolerating halide, hydroxy, amino, ether, ester, lactone, amide and heteroaromatic functionalities. These reactions offered a direct access to a variety of N-borylamines RN(H)BPin
We have developed a simple and direct method for the synthesis of arylethers by reacting alcohols/phenols (ROH) with aryl ammonium salts (ArNMe3+), which are readily prepared fromanilines (ArNR′2, R′=H or Me). This reaction proceeds smoothly and rapidly (within a few hours) at room temperature in the presence of a commercially available base, such as KOtBu or KHMDS, and has a broad substrate scope