Synthesis of the hepatocarcinogen N-methyl-4-aminoazobenzene with tritium in the prime ring

✍ Scribed by Jen-Kun Lin; James A. Miller

• Publisher: John Wiley and Sons
• Year: 1969
• Tongue: French
• Weight: 215 KB
• Volume: 5
• Category: Article
• ISSN: 0022-2135
• DOI: 10.1002/jlcr.2590050307

✦ Synopsis

The new compound N-methyl-4-nitrosoacetanilide w a ~. coupled with ~niIine-~H(ring-G) in ethanol-acetic acid and the resulting azoamide was hydrolyzed in alkali to give a high yield o j N-methyl-4-aminoazobenzene labelled in the prime ring.

INTRODUCTION.

N-Methyl-4-aminoazobenzene, a hepatocarcinogen in the rat, and related dyes are converted in this species into metabolites which react with hepatic proteins and nucleic acids to form covalently bound derivatives (1-3). These bound derivatives may play a role in the carcinogenic process induced by these dyes (1-3). For further studies in vivo N-methyl-4-aminoazobenzene of high specific activity with label in the prime ring was required. Synthesis of this dye in high yield was achieved by coupling excess N-methyl-4-nitrosoacetaniiide with at~iIine-~H(ring-G). After removal of the N-acetyl group with alkali the labelled aminoazo dye was purified by column chromatography. Attempts to prepare this dye directly by coupling N-methyl-4-nitrosoaniline (4) with aniline were unsuccessful. EXPERIMENTAL.

N-Methyl-4-nitroacetanilide.

N-Methylaniline (20 g) was added to 40 ml of acetic anhydride and the mixture allowed to stand at room temperature for 20 hours. Benzene (100 ml) was added and the mixture evaporated to dryness in vucuo at 50° C .