5- aminosalicylate

Aminosalicylic acid (5-amino-2-hydroxybenzoic acid) [89-57-6] M 153.1, m 276-280 , 283 (dec), pK 2.74 (CO2H), pK 5.84 (NH2). Cryst as needles from H2O containing a little NaHS03 to avoid aerial oxidation to the quinone-imine. The Me ester gives needles from C6H6, m 96°, and the hydrazide has m 180-182° (From H2O). [Fallab et al. Helv Chim Acta 34 26 1951, Shavel J Amer Pharm Assoc 42 402 1953.]... 

Rnss R, C Muller, H-J Knackmuss, A Stolz (1994) Aerobic biodegradation of 3-aminobenzoate by Gram-negative bacteria involves intermediate formation of 5-aminosalicylate as ring-cleavage substrate. FEMS Microbiol Lett 122 137-144. 

The degradation of salicylate to catechol is initiated by monooxygenation accompanied by decarboxylation (salicylate-l-hydroxylase), and two different and independent salicylate hydroxylases have been found in the naphthalene-degrading Pseudomonas stutzeri ANIO (Bosch et al. 1999). Alternatively, in Rhodococcus sp. strain B4, salicylate is hydroxylated to 2,5-dihydroxybenzoate by salicylate-5-hydroxylase (Grand et al. 1992). An alternative occurs for 5-hydroxy- and 5-aminosalicylate in Pseudaminobacter salicylatoxidans in which ring fission is accomplished directly (Hintner et al. 2001). 

An analogous pathway is used for the degradation of 5-aminosalicylate that is an intermediate in the degradation of 6-aminonaphthalene-2-sulfonate. Direct ring fission of both 5-aminosalicylate and 5-hydroxysalicylate can be accomplished by a salicylate 1,2-dioxygenase in Pseudaminobacter salicylatoxidans (Hintner et al. 2001). 

Aromatic azo compounds, many of which are sulfonated, are components of many commercially important dyes, colorants, and pigments, so that attention has been directed to their degradation and transformation. These compounds are often considered recalcitrant, although then-transformation has been accomplished by reduction to amines with scission of the Ar-N=N-Ar bond to produce arylamines. The amines may then be degraded, for example, 6-aminonaphthalene-2-sulfonate by dioxygenation and ring fission to 5-aminosalicylate (Hang et al. 1991). This is then... 

Stolz A, H-J Knackmuss (1993) Bacterial metabolism of 5-aminosalicylic acid enzymatic conversion to malate, pyruvate and ammonia. J Gen Microbiol 139 1019-1025. 

Ahnfelt-Ronne, 1., Nielsen, O.H., Christensen, A., Langholz, E., Binder, V. and Riis, P. (1990). Clinical evidence supporting the radical scavenger mechanism of 5-aminosalicylic acid. Gastroenterology 98, 1162-1169. 

Baughan, C.A., Canney, P.A., Buchanan, R.B. and Pickering, R.M. (1993). A randomised trial to assess the efficacy of 5-aminosalicylic acid for the prevention of radiation enteritis. Clin. Oncol. Roy. Coll. Radiol. 5, 19-24. 

Aminosalicylate oxidation by activated leukocytes and protection of cultured cells from oxidative damage. Biochem. Pharm. 36, 2467-2472. 

Grisham, M.B., Ryan, E. and Von Ritter, C. (1987). 5-Aminosalicylic acid scavenges hydroxyl radical and inhibits myeloperoxidase activity. Gastroenterology 92, 1416. 

Pallapies, D., Peskar, B.A. and Peskar, B.M. (1992). 5-Aminosalicylic acid (5-ASA) inhibits the activity of nitric oxide (NO) contribution to its anti-inflammatory effects Gastroenterology 102, A677. 

Saibil, F.G., Sherman, J.A., Heller, D.J., Liepert, T.T. and Janossy, T. (1990). Microcirculatory and cytoprotective effects of 5-aminosalicylic acid (5-ASA) in gastric and jejunal mucosae. Gastroenterology 98, A201. 

Williams, J.G. and Hallett, M.B. (1989).Effect of sulphasalazine and its active metabolite, 5-aminosalicylic acid, on toxic oxygen metabolite production by neutrophils. Gut 30, 1581-1587. 

Yamada, T., Volkmer, C. and Grisham, M.B. (1990). Antioxidant properties of 5-aminosalicylic acid, potential mechanism for its anti-inflammatory activity. In Trends in Inflammatory Bowel Disease Therapy , (ed. C.J. Williams) pp. 73-84. Kluwer Academic Publishers, Lancaster. 

Scavenging effect of 5-aminosalicylic acid on neutrophil-derived oxidants. Biochem. Pharmacol. 41, 1001-1006. 

III. Amines 5-Aminosalicylic acid Azo bound with sulfahydrine, 4-aminobenzoyl-(3- 23,32,33... 

OAT Olsson, LA Svensson. Treatment of chronic ulcerative-colitis with poly-ASA—A new nonabsorbable carrier for release of 5-aminosalicylate in the colon. Pharm Res 19-23, 1984. 

U Klotz. Clinical pharmacokinetics of sulfasalazine, its metaboliters and other prodrugs of 5-aminosalicylic acid. Clin Pharmacokin 10 285-302, 1985. 

Pitcher MC, Beatty ER, Cummings JH The contribution of sulphate reducing bacteria and 5-aminosalicylic acid to faecal sulphide in patients with ulcerative colitis. Gut 2000 46 64-72. 

The answer is b. (Hardman, p 1061.) Sulfasalazine consists of sul-fapyridine with 5-aminosalicylic acid linked by an azo- bond. This bond is broken by bacteria that release the salicylic acid, which is believed to be the active agent. Sulfa drugs or salicylic acid used alone is not as effective. The mechanism of action is unknown, but it is believed to be protective action on the mucosa by inhibition of the synthesis of prostaglandins and leukotrienes. 

Olsalazine Dipentum Dimer of 5-aminosalicylic acid 1.5-3 g Colon... 

Acetyl-5-aminosalicylic acid +0.8 (calomel) glassy carbon 262... 

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