74827-90-0

Upstream product

• 108-68-9 3,5-Dimethylphenol 
• 6337-56-0 N-(4-hydroxy-2,6-dimethylphenyl)acetamide 
• 3096-70-6 3,5-dimethyl-4-aminophenol 
• 74827-88-6 N-acetyl-3,5-dimethyl-1,4-benzoquinone imine 

Relevant academic research and scientific papers

Hydrolysis of N-Acetyl-p-benzoquinone Imines: pH Dependence of the Partitioning of a Tetrahedral Intermediate

The hydrolysis reactions of N-acetyl-p-benzoquinone imine, 1a, and its 3,5- and 2,6-dimethyl analogues, 1b and 1c, in the pH range 0.3-10.5 are described.At pH 6.0 the carbinolamide intermediates 2a-c can be detected by 1H NMR, UV, and HPLC methods.The pH-dependent partitioning of 2a and 2c can be monitored since the reversion of these intermediates to the protonated N-acylimines 5a and 5c leads to products of the conjugate attack of Cl(-), the 3-chloroacetaminophen derivatives 4a and 4c.A mechanism for the hydrolysis of 1a-c (Scheme I) is proposed which accurately predicts the time dependence of the formation of 2 and the final hydrolysis products, the p-benzoquinones 3, and 4.The alternative O-protonation mechanism (Scheme II) is tentatively rejected on the basis of substituent effect data.The relationship of the hydrolysis reactions of 1a-c to those of ordinary imines is discussed.

Studies on the mechanism of toxicity of acetaminophen. Synthesis and reactions of N-acetyl-2,6-dimethyl- and N-acetyl-3,5-dimethyl-p-benzoquinone imines

N-Acetyl-2,6-dimethyl-p-benzoquinone imine and N-acetyl-3,5-dimethyl-p-benzoquinone imine were prepared from 2,6-dimethylacetaminophen and 3,5-dimethylacetaminophen by oxidation with lead tetraacetate. Reaction of N-acetyl-2,6-dimethyl-p-benzoquinone imine with hydrochloric acid gave 3'-chloro-2',6'-dimethyl-4'-hydroxyacetanilide, whereas ethanethiol, aniline, and ethanol gave tetrahedral adducts resulting from addition to the imine carbon. Water gave 2,6-dimethyl-p-benzoquinone. With N-acetyl-3,5-dimethyl-p-benzoquinone imine, water and aniline gave substitution on the imine carbon, yielding 2,6-dimethyl-p-benzoquinone and 3,5-dimethyl-N-phenyl-p-benzoquinone imine, respectively. Ethanethiol gave 3',5'-dimethyl-2'-(ethylthio)-4'-hydroxyacetanilide. The toxicity of 2,6-dimethylacetaminophen and 3,5-dimethylacetaminophen was examined histologically in mice and rats. 3,5-Dimethylacetaminophen was slightly more nephrotoxic but showed a similar hepatotoxicity to acetaminophen. 2,6-Dimethylacetaminophen, like N-methylacetaminophen, showed very little tissue damage.