4-Amino-6-nitro-o-cresol

No amino derivatives of DNOC were detected in the blood, bone marrow, or adipose tissue, but 6-amino-4-nitro-o-cresol was detected in the liver, kidneys, and brain of rabbits that received an oral dose of 18 mg/kg DNOC (Truhaut and De Lavaur 1967). No 4-amino-6-nitro-o-cresol was detected in these tissues. Both DNOC and 6-amino-4-nitro-o-cresol were recovered from the urine as 25-38% of the dose. Smaller amounts of 4-amino-6-nitro-o-cresol were also detected in the urine. Further... 

Within 2 days after receiving a single dose of 20-30 mg/kg DNOC, Chinchilla rabbits excreted <20% of the dose as metabolites (Smith et al. 1953). Unchanged DNOC accounted for 5% of the dose and conjugated DNOC accounted for 1%. Derivatives of 6-amino-4-nitro-o-cresol comprised 11-12% of the dose, including 6-acetoamido-4-nitro-o-cresol (1-1.5% of the dose), O- conjugates of this metabolite (10% of the dose), and unspecified amounts of 3-amino-5-nitro-salicylic acid and derivatives of 4-amino-6-nitro-o-cresol that were also excreted in the urine. 

Studies in animals reveal differences among species and between animals and humans. Maximum blood DNOC concentrations of 72.2 pg/g at 6 hours after the last dose of 20 mg/kg/day for 9 days and 105 pg/g at 3.5 hours after a single dose of 30 mg/kg DNOC were found in rats (King and Harvey 1953b). When rabbits were similarly treated, peak values were 54.7 pg/g at 4.5 hours after multiple doses of 25 mg/kg/day DNOC and 49.5 pg/g at 6 hours after a single dose of 30 mg/kg. Blood DNOC levels of 25, 34, and 50 pg/g were detected in rabbits given single oral doses of 10, 15, or 18 mg/kg DNOC, respectively (Truhaut and De Lavaur 1967). Urinary excretion of DNOC and its metabolite, 6-amino-4-nitro-o-cresol, accounted for 25-38% of the 10-15 mg/kg/day doses in 3 days. Of this, 87-97% was excreted in the first day. 

Rat cecal contents were incubated with DNOC to determine whether the compound is metabolized in the large intestine (Ingebrigtsen and Froslie 1979). About 80% of DNOC was metabolized to 6-amino-4- nitro-o-cresol within 1 hour. Within the next 12 hours, 90% of this metabolite was further reduced to 2-methyl-4,6-diaminophenol. The authors determined that the cecal microorganisms in rats were responsible for the reduction of DNOC and its subsequent metabolites to diamino derivatives. Although not detected in humans or other monogastrics, these diamino derivatives are formed in sufficient quantities in ruminants to cause methemoglobinemia, which can be fatal in these species (Froslie 1973). 

DNOC and its metabolite, 6-amino-4-nitro-o-cresol, which were detected in the urine of rabbits, made up 25-38% of the 10-15 mg/kg DNOC dose (Truhaut and De Lavaur 1967). Of this amount, 82-97% was eliminated within 1 day, and the rest was excreted within 2-3 days. As the dose of DNOC increased from 10 to 20 mg/kg, the ratio of 6-amino-4-nitro-o-cresol to DNOC in urine increased from 0.66 to 1.47 when measured at 2.5-3.75 hours after the dose. These ratios may be useful biomarkers of exposure to DNOC if the same phenomenon occurs in humans. 

Metabolites of DNOC are more likely to be detected in the urine than in blood. The ratio of urinary DNOC to 6-amino-4-nitro-o-cresol may be a useful biomarker in humans (Truhaut and De Lavaur 1967). However, no studies were located regarding urinary metabolites of DNOC in humans, and toxicokinetic data show that humans eliminate DNOC more slowly than animals (King and Harvey 1953b). 

C7H6BrN03 a-bromo-4-nitro-o-cresol 772-33-8 25.00 1.7038 2 10333 C7H6IN02 2-amino-5-iodobenzoic acid 5326-47-6 25.00 1.8886 2... 

Soil/Plant. In plants and soils, the nitro groups reduced to amino groups (Hartley and Kidd, 1987). When 4,6-dinitro-o-cresol was statically incubated in the dark at 25°C with yeast extract and settled domestic wastewater inoculum, no significant biodegradation and necessary acclimation for optimum biooxidation within the 4-week incubation period was observed (Tabak et al., 1981). 

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