5-Aminosalicyclic acid

A mixture of 20.0 g (0.076 mole) of 2-phenacyl-l-tetralone, 11.6 g (0.076 mole) of 5-aminosalicyclic acid, and 70 ml of glacial acetic acid was heated under reflux for 4 hours, cooled, diluted with 10 ml of water and filtered. The filter cake was washed with water and dried to provide 15.5 g of solid, 5-(4,5-dihydro-2-phenyl-3H-benz[e]indol-3-yl)-2-hydroxy-benzoic acid. MP 215°-218°C. Recristallization from benzene-cyclohexane gave 6.5 g (22%) of yellow crystals, MP 245°-247°C. 

I. Cendrowska, M. Drewnowska, A. Grzeszkiewicz, and K. Butkie-wicz, Investigation of the stability of 5 aminosalicyclic acid in tablets and suppositories by HPLC, J. Chromatogr., 509 195 (1990). 

It has a suppressive effect on ulcerative colitis. This therapeutic action may perhaps be attributed to a local immimosuppressive effect. Salazosulfapyridine ultimately releases sulfapyridine and 5-aminosalicyclic acid in the colon with the aid of bacterial enzymes. It often imparts a yellow colour to alkaline urine. 

The mechanism of decarboxylation of acids containing an amino substituent is further complicated by the possibility of protonation of the substituent and the fact that the species NH2ArCOOH is kinetically equivalent to the zwitterion NHj ArCOO. Both of these species, as well as the anion NH2 ArCOO" and even NH3 ArCOOH must be considered. Willi and Stocker644 investigated by the spectroscopic method the kinetics of the acid-catalysed decarboxylation of 4-aminosalicyclic acid in dilute hydrochloric acid, (ionic strength 0.1, addition of potassium chloride) and also in acetate buffers at 20 °C. The ionisation constants K0 = [HA][H+][H2A+] 1 (for protonation of nitrogen) and Kx = [A"][H+] [HA]-1, were determined at /i = 0.1 and 20 °C. The kinetics followed equation (262)... 

Other chemical reactions, such as hydration, decarboxylation, or pyrolysis, are also potential routes for drug degradation. For example, cyanocobalamin may absorb about 12% of water when exposed to air, and p-aminosalicyclic acid decomposes with evolution... 

The stable multi-phases are found not only in polyampholyte gels but also in a homopolymer gel, e.g. poly(/V-acryloyl-4-aminosalicyclic acid) gel [130], and... 

We have used the reaction extensively to prepare the indole moiety of several natural products. For example, the key step in the synthesis of the bacterial coenzyme methoxatin (36) is the formation of the indole (35) by intramolecular nitrene insertion from the azide (34), readily prepared from commercially available 4-aminosalicyclic acid. The third ring was annelated onto the indole (35) using conventional chemistry to give, after oxidation to the orrho-quinone, the natural product (36). 

Dicoumarol, warfarin + p-aminosalicyclic acid Increased anticoagulant serum levels with risk of haemorrhage Displacement from protein Monitor anticoagulant effect, especially with initiation or cessation of therapy... 

Shuqin K, Haishang D, Peiyi X, et al. 1992. A report of two cases of chronic serious manganese poisoning treated with sodium para-aminosalicyclic acid. Br J Ind Med 49 66-69. 

A fluoroquinolone cycloserine capreomycin or kanamycin or amikacin efliionamide para-aminosalicyclic acid clofazimine Clarithromycin or azithromycin ethionamide ... 

EDTA = ethylenediaminotetraacetic acid, NTA = nitrilotriacetic acid, DMA = dimethyl-anthranilic acid, PAS = p-aminosalicyclic acid. 

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