Sulfonic hydrolytic cleavage

With aldicarb, primary metabolic attack is again by oxidation and hydrolysis. Hydrolytic cleavage yields an oxime and represents a detoxication. Oxidation to aldicarb sulfoxide and sulfone, however, yields products that are active anticholinesterases. Carbofuran is detoxified by both hydrolytic and oxidative attack. 

Antibacterial sulfonamides contain two N-atoms, the sulfonamido (N1) and the para primary amino (N4). The sulfonamido group, in contrast to a carboxamido group, is chemically and metabolically stable. In other words, hydrolytic cleavage of sulfonamides to produce a sulfonic acid and an amine has never been observed. We, therefore, focus our discussion on the primary amino group, acetylation of which is one of the major metabolic pathways for some sulfonamides. Hydrolysis of the N4-acety luted metabolites back to the parent sulfonamide can occur in the liver, kidney, and intestinal tract. The reaction is strongly influenced by the structure of the parent amine e.g., N4-acetylsulfisoxazole (4.121) was deacetylated by intestinal bacteria whereas /V4-acctyIsulI anilamide (4.122) under identical conditions was not [78][79],... 

Another concern for polystyrene- and some aromatic-based PEMs is hydrolysis of fhe sulfonic acid group from aromatic rings as well as hydrolytic cleavage of polymer backbone under fuel cell conditions for aromafic polymers including polyimides, poly(arylene ethers), poly(ether ketones), and poly(ether sulfones). It is well known that the sulfonation of aromafic rings is a reversible process especially at low pH and at elevated temperature (Scheme 3.3). The reversibility of sulfonation, for example, is used in fhe preparafion of trinitrotoluene or picric acid. Por the simplest membrane of the class of arylsulfonic acids (i.e., benzenesulfonic acid), fhe reacfion occurs upon freatment with a stream of superheated steam at 180°C.i ... 

Kynureninase catalyzes the hydrolytic cleavage of both kynurenine and 3-hydro-xykynurenine to generate anthranilic acid and 3-hydroxyanthranilic acid, respectively [55]. The majority of inhibitors of kynureninase are substrate based and are designed based on the postulated transition state intermediate where water attacks the benzoyl group carbonyl through a PLP-dependant mechanism. The hydroxy (16 = 0.3 pM) and sulfone (17 IC50 =11 pM) derivatives have... 

Membrane instability was believed to result from hydrolytic cleavage of sulfate and sulfonate esters in the sulfonated polyfurane resin. This hydrolysis would entail some depolymerization of the resin and concurrent formation of ionic sulfonate groups, causing the membrane to absorb water and swell in monovalent salt solutions. Oxidation by dissolved oxygen is another potential... 

Soil The sulfoxide group is oxidized to the sulfone and oxidative and hydrolytic cleavage of the side chain gives dimethylphosphoric and phosphoric acids (Hartley and Kidd, 1987). Oxamyl was degraded by the microorganism Pseudomonas putida in a laboratory study using cultured bacteria (Zeigler, 1980). 

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