Sulfonamides solubility

Concomitant use of urine-acidifying agents (ammonium chloride, ascorbic acid) decreases urine pH and sulfonamide solubility, thus increasing risk of crystalluria. Concomitant use with antibiotics that alter intestinal flora may interfere with conversion of sulfasalazine to sulfapyridine and 5-aminosalicylic acid, decreasing its effectiveness. 

Sulfonamides are weak acids and their lower-molecular members are soluble in 5% NaOH. Sulfonamides soluble in 5% NaOH can be easily hydrolyzed,. 

Sulfonamide groups can be introduced into phthalocyanines to make them soluble in alcohols and glycol ethers. Their main appHcations are transparent paints, flexo and gravure printing inks, wood stains, plastics, and ballpoint inks. This includes products Hke Solvent Blue 24 (Cl 74380),... 

Other Infections. The slowly excreted sulfonamides (eg, sulfamethoxypyrida2ine, sulfadimethoxine) are used for treatment of minor infections such as sinusitis or otitis, or for prolonged maintenance therapy. Soluble sulfonamides are sometimes used for proto2oal infections in combination with other agents. Pyrimethamine, combined with sulfonamides, has been used for toxoplasmosis or leishmaniasis, and trimethoprim with sulfonamides has been used in some types of malaria. In nocardiosis, sulfonamides have been used with cycloserine [68-41-7] (17). 

The resulting acetyl compound is usually hydrolyzed with aqueous alkaU to give the free amine. Other A/-acyl derivatives may be used, particularly for the less soluble succinyl and phthaloyl products. The use of -nitrobenzenesulfonyl chloride, followed by reduction of the nitro to an amino function, is much more expensive and is rarely used. A/-Acetylsulfanilyl chloride [121 -60-8] is obtained by the chlorosulfonation of acetanilide [103-84-4] which is the basic material for most of the sulfonamides. 

Sulfonamidates. Chloramine-T, A/-chloro-A/-sodiomethylbenzenesulfonamidate ttihydrate [127-65-1], CH3C3H4S02NClNa-3H20, a white to slightly yellow soHd, effloresces in air losing chlorine, becoming less soluble in water (71). It has a mp of 175°C, an av CI2 of 25%, and is moderately soluble... 

Developing agents must also be soluble in the aqueous alkaline processing solutions. Typically such solutions are maintained at about pH 10 by the presence of a carbonate buffer. Other buffers used include borate and, less frequendy, phosphate. Developer solubiUty can be enhanced by the presence of hydroxyl or sulfonamide groups, usually in the A/-alkyl substituent. The solubilization also serves to reduce developer allergenicity by reducing partitioning into the lipophilic phase of the skin (46). 

The use of images in terms of oxidized developer to release dyes initially immobilized through a sulfonamide linkage has been described (33). In one approach color coupling leads to ting closure and concomitant release of an alkah-soluble dye (eq. 1). 

A second approach utilizes the oxidation of alow mobiUty substituted 4-hydroxydiphenylamine to which an image dye is linked through a sulfonamide group. Oxidation and hydrolysis result in ting closure and release of the alkaU-soluble dye (eq. 2). 

Amides are stable compounds. The lower-melting members (such as acetamide) can be readily purified by fractional distillation. Most amides are solids which have low solubilities in water. They can be recrystallised from large quantities of water, ethanol, ethanol/ether, aqueous ethanol, chloroform/toluene, chloroform or acetic acid. The likely impurities are the parent acids or the alkyl esters from which they have been made. The former can be removed by thorough washing with aqueous ammonia followed by recrystallisation, whereas elimination of the latter is by trituration or recrystallisation from an organic solvent. Amides can be freed from solvent or water by drying below their melting points. These purifications can also be used for sulfonamides and acid hydrazides. 

Another point for structural diversification is the sulfonamide group. Imai had already shown that a wide variety of groups could be introduced at this position to optimize the reaction. Since a wide variety of sulfonyl chlorides are commercially available, a number of different types of groups could be examined (Scheme 3.34). Testing of a variety of aryl and alkyl groups on the 1,2-cyclohexanediamine backbone demonstrates that the simple methanesulfonamide 122 is clearly superior or equal to many other analogs in the cyclopropanation of cinnamyl alcohol (Table 3.11). Another concern which was directly addressed by this survey was the question of catalyst solubility. 

The treatment of sulfonyl chlorides with ammonia or amines is the usual way of preparing sulfonamides. Primary amines give N-alkyl sulfonamides, and secondary amines give N,N-dialkyl sulfonamides. The reaction is the basis of the Hinsberg test for distinguishing between primary, secondary, and tertiary amines. N-Alkyl sulfonamides, having an acidic hydrogen, are soluble in alkali, while N,N-dialkyl sulfon-... 

Among pharmaceuticals, antibiotics have become of special concern in recent years. The reason is that these substances are continuously being introduced into the environment and may spread and maintain bacterial resistance in the different compartments. Sulfonamides are very commonly used antimicrobials in humans but mainly in veterinary medicine, due to their broad spectrum of activity and low cost, being the second most widely used veterinary antibiotic in the EU. Their occurrence has been reported in all kinds of water matrices their high excretion rates (after their intake by humans of livestock) and high water solubility make them very ubiquitous and persistent pollutants in the environment. 

In a recent study, the group of Buijsman presented a microwave-mediated preparation of a different N-imidazolium-based ionic analogue of the well-known AMEBA solid support (Scheme 7.93). With this soluble support, a set of various sulfonamides and amides was prepared, and furthermore the use of this novel linker in the synthesis of a potent analogue of the antiplatelet drug tirofiban was presented [106]. 

Could not be determined with accuracy because of the poor solubility of sulfonamides in benzene... 

Sulfonamides are historically important but have been largely replaced by other newer antibacterials. They are still used in urinary infections and in the treatment of bronchitis. The danger of crystal formation in the kidneys is circumvented by administering a mixture of sulfonamides. This changes the solubility characteristics but still has an effect on the bacteria. 

Porphyria In patients with porphyria, these drugs have precipitated an acute attack. Photosensitivity Photosensitization (photoallergy or phototoxicity) may occur. Renal/Hepatic function impairment Jse with caution. The frequency of renal complications is considerably lower in patients receiving the more soluble sulfonamides (sulfisoxazole and sulfamethizole). 

Sulfonamides are rather slowly absorbed with peak blood levels 2-6 h after oral intake. Intravenous preparations are sometimes used with comatose patients. Sulfonamides are distributed throughout the body, including the CNS. Binding to serum proteins varies from 20% to 90%. Several sulfonamides are acetylated in the liver followed by excretion in the urine. Soluble sulfonamides are eliminated by glomerular filtration. 

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