A-acetyl-p-aminophenol

Chemical A/-Acetyl-p-aminophenol Generic (Nonproprietary) Acetaminophen Trade/Brand-Name (Proprietary) Tylenol, Panadol, many others... 

The most widely used analgesic is Paracetamol, or A-acetyl-p-aminophenol (155), also known as acetaminophen (US), and Tylenol (with codeine), and synthesized from nitrobenzene. Care has to be taken with use hepatoxicity can develop with overdoses. 

C. M-acetyl benzoquinoneimine is toxic, whereas acetaminophen glu-curonide, acetaminophen sulfate, and acetaminophen glutathionate are nontoxic acetaminophen conjugates. A -acetyl-p-aminophenol is another name for acetaminophen. 

In order to avoid citation of difficult chemical names, generic names came into being. However, in the beginning different names were independently assigned to the same substance in different countries. For example, not everybody would know that acetaminophen, 7V-(4-hydroxyphe-nyl)acetamide, 4 -hydroxyacetanilide, p-acetamidophenol, A -acetyl-p-aminophenol, acetomenophen and paracetamol are the same substance (see Fig. 41.2). 

To the filtrate obtained, there are then added about 0.2 gram of sodium hydrosulfite or sodium sulfite and 15.0 grams of anhydrous sodium acetate in about 27 grams of acetic anhydride at 40°C. The reaction mixture formed is cooled to 8° to 10°C with stirring and held at this temperature for 60 minutes. A crystalline precipitate of about 27 grams of N-acetyl-p-aminophenol is obtained melting at 169°-171°C. This is equivalent to a yield of 85%. 

Various hydroxyl and amino derivatives of aromatic compounds are oxidized by peroxidases in the presence of hydrogen peroxide, yielding neutral or cation free radicals. Thus the phenacetin metabolites p-phenetidine (4-ethoxyaniline) and acetaminophen (TV-acetyl-p-aminophenol) were oxidized by LPO or HRP into the 4-ethoxyaniline cation radical and neutral V-acetyl-4-aminophenoxyl radical, respectively [198,199]. In both cases free radicals were detected by using fast-flow ESR spectroscopy. Catechols, Dopa methyl ester (dihydrox-yphenylalanine methyl ester), and 6-hydroxy-Dopa (trihydroxyphenylalanine) were oxidized by LPO mainly to o-semiquinone free radicals [200]. Another catechol derivative adrenaline (epinephrine) was oxidized into adrenochrome in the reaction catalyzed by HRP [201], This reaction can proceed in the absence of hydrogen peroxide and accompanied by oxygen consumption. It was proposed that the oxidation of adrenaline was mediated by superoxide. HRP and LPO catalyzed the oxidation of Trolox C (an analog of a-tocopherol) into phenoxyl radical [202]. The formation of phenoxyl radicals was monitored by ESR spectroscopy, and the rate constants for the reaction of Compounds II with Trolox C were determined (Table 22.1). 

Figure 29.7. Urinary excretion of proximal tubular enzymes following para-aminophenol (PAP) administration to female Sprague-Dawley rats. Rats received PAP (300mg/kgip) and urine was collected for 24 hr following treatment. Urine was assayed for activities of y-glutamyl transpeptidase (GGTP, O), trehalase (TRE, ), and A-acetyl-P-glucosaminidase (NAG, ). Data are expressed as a percentage of enzyme excretion in rats treated with saline. Each data point represents the mean standard error of at least four determinations. GGTP and TRE are enzymes located primarily on the brush border of proximal tubule cells, and NAG is an intracellular enzyme.

Acetaminophen (N-acetyl-p-aminophenol, paracetamol) is an analgesic marketed under a variety of brand names including Tylenol , Calpol , and Panadol . Preparation of the API is described in U.S. 2,998,450 (to Warner Lambert). U.S. 4,474,985 (to Monsanto) describes a process for improving product quality and shelf life. U.S. 5,856,575 (to Council of Scientific Industrial Research) describes an alternative process. Estimate the cost of production by each route. 

Relative to the fate in humans of the l pes of compounds just discu.s.sed. Brudie and Axelrod " " point out that acet-anilid and phenacetin are metabolized by two different routes. Acctaniiid is metabolized primarily to Af-acetyl-p-aminophenol and acetaminophen and only a small amount to aniline, which they showed to be the precursor of phenyl-hydroxylamine. the compound re.sponsible for methcmoglobin formation. Phenacetin is mostly dccthylated to acetaminophen. whereas a small amount is convened by dcacctylation top-phenetidinc. also responsible for methemoglobin formation. With both acetanilid and phenacetin. the metabolite acetaminophen is believed to be responsible for the analgesic activity. Because of the toxicity described above, both are no longer available, replaced primarily by acetaminophen. 

Synonyms APAP 4 -Hydroxyacetanilide p-Hy-droxyacetanilide Acetamide N-(4-hydroxyphenyl) N-Acetyl-p-aminophenol N-Acetyl-p-aminophe-nol p-Acetamidophenol 4-Acetamidophenol 4-Acetaminophenol Paracetamol Tylenol Chemical/Pharmaceutical/Other Class Acetaminophen is a synthetic nonopioid congener of acetanilide in the p-aminophenol class Chemical Eormula C8H9NO2... 

Phenazopyridine is absorbed through the gastrointestinal tract. It is metabolized rapidly, producing aniline, 2,3,6-triaminopyridine, p-aminophenol, and N-acetyl-/7-aminophenol. Renal clearance is the major route of elimination. Approximately 90% of a therapeutic dose is excreted in the urine within 24 h, with 41% as phenazopyridine, 24% as p-amino-phenol, 18% as N-acetyl-p-aminophenol, and 6.9% as aniline. The color of the urine changes to orange or red. 

A medication s chemical name is used by scientists who work at the chemical level of the medication. The chemical name identifies the medication s chemical elements and compounds for example, N-acetyl-p-aminophenol. 

B. Aniline Derivatives - A structure-activity study of a new series of alkoxyaniline derivatives has been reported along with a detailed workup of one of them . This compound (XII) appears to have good analgesic and anti-inflammatory activity, associated with some CNS depressant effects. An antidiuretic effect was described for acetaminophen 9 a d it was suggested that this drug might be a useful substitute for vasopressin in certain patients with diabetes insipidus. Evidence was also presented to show that acetophenetidin has antipyretic activity which is not dependent on metabolism to N-acetyl-p-aminophenol. 

The interesting observation that the analgesic acetaminophen (N-acetyl-p-aminophenol) accelerates net water flow across the Isolated toad bladder led to its trial in patients with diabetes insipidus.a single dose (1.2 to 2,k g.) produced a marked fall in urinary excretion and a rise in osmolality. It was suggested that acetaminophen may be a useful substitute for vasopressin in diabetes inslpidxis. 

Each dose of a nighttime cold medicine contains 1000 mg of the analgesic acetaminophen. Acetaminophen, or N-acetyl-p-aminophenol, has the general formula CgHgNO. 

A stilbene polymer (Gn-3) isolated from Gnetum parvifolium inhibited the development of liver injury in mice caused by CCl4j N-acetyl-P-aminophenol (APAP) and Bacillus Calmette-Guerin (BCG) plus bacterial lipopolysaccharide (LPS) at a dose of 50 mg-kg d 1 sc administered for 3 d thus Gn-3 was found to have liver protective effects [74]... 

A chemical name looks strange to anyone who isn t a chemist and is difficult for most of us to pronounce. That s why names other than the chemical name are given to a dmg. Here is the chemical name for a commonly used dmg N-acetyl-p-aminophenol. 

Acetaminophen (paracetamol, N-acetyl-p-aminophenol APAP) is a widely used over-the-counter analgesic and antipyretic dmg (Bessems and Vermeulen 2001 James et al. 2003b Prescott and Critchley 1983). At therapeutic doses, it is believed to be safe, having analgesic and antipyretic effects similar to those of aspirin and ibuprofen. Unlike these other drugs, acetaminophen has only weak antiinflammatory properties. 

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