Sulfonamide linkage

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). 

In addition, desulfonation generally has to be taken into account with benzamides and phthalimides that are sulfonated at the amine subunit. The sulfonamide linkage proved to be stable with sulfonated and nonsul-fonated sulfonamides. Compounds with electron-withdrawing substituents at the sulfonic acid-bearing ring were more stable with respect to the hydrolysis of sulfonic acid groups. 

Miller s biomimetic approach inspired Ishihara [234] to develop a minimal artificial acylase for the KR of mono-protected cw-l,2-diols and A-acylated 1,2-amino alcohols. Derived from (S)-histidine, Ishihara s organocatalyst contains only one stereogenic centre and incorporates a sulfonamide linkage in place of a polypeptide chain to allow the NH group to engage as an H-bond donor with the substrates (Fig. 13) [234]. 

Attachment of chlorosulfonated MPc by sulfonation and sulfonamide linkage to mac-roreticular polystyrenes led to a polymer containing 0.0027 to 0.035% (49), 50) (Eq. 19) Here, the MPc are mainly aggregated at the edges of the beads. The activity of the polymers for the oxidation of cyclohexene at 351 K compared with low molecular... 

A number of related catenanes, including systems assembled directly from commercially available precursors and a system based on sulfonamide linkages, have also been described. 

The tetraarylporphyrin ligand was bonded to macroreticular polystyrene through carboxamide and sulfonamide linkages. The aminopoly-styrene used for the preparation of these materials was obtained from unfunctionalized polystyrene by nitration, followed by reduction of the nitro groups with stannous chloride. This aminopolystyrene was then coupled with the tetra(p-chlorosulfophenyl)porphine and the tetra(p-chlorocarbonyl)-phenylporphine obtained from the respective adds or acid salts to give the sulfonamide-linked and the carboxamide-linked... 

Synthetic studies focused on the bicyclic heterocycle led to the discovery of a new sub-class of sulfonamides where the triazolo[l,5-a]pyrimidine ring was replaced with a triazolo[l,5-c]pyrimidine ring. Further investigations led to the development of diclosulam (3) and cloransulam-methyl (4) for broadleaf weed control in soybeans, and florasulam (5) for broadleaf weed control in cereals. To fully explore this sub-class of sulfonamides, an investigation was initiated to determine if reversing the sulfonamide linkage (6) would lead to compounds with the spectrum of activity on weeds and crop selectivity different from 3, 4, and 5. 

Because azo dyes, as amaranth, are the most widely used food colorants and are water soluble, they were bonded to selected polymers via a sulfonamide linkage. However, the azo linkages in the dyes themselves were unstable to intestinal microbial action and do not meet the requirements of biological stability because they are cleaved in the gut to yield absorbable aromatic amines. Hence a variety range of chromophore classes have been reported to be incorporated into polymers. For the anthraquinone class of chromophores, the basic water insolubility was changed by converting a portion of the backbone to sulfonic acids that impart anionic solubilizing functions. However, this meant that fewer chromophores could be attached and less intense colors would result. 

Write the structure of the material containing sulfonamide linkages that might be obtained upon polymerization of 4-aminobenzenesulfonyl chloride. 

Kaur, S., G Florio, and D. Michalak, Cross-Linking of Sulfonated Styrene-Ethylene/Butylene-Styrene Triblock Polymer via Sulfonamide Linkages. Polymer, 2002.43 5163-5167. 

Fluorinated tertiary amines with a sulfonamide linkage are obtained by a reaction with a fluorinated alkanesulfonyl chloride and a primary or a secondary amine. For example, l-amino-3-dimethylaminopropane reacts with perfluo-roalkylethanesulfonyl chloride to give a fluorinated tertiary amine which is quat-emized to yield a betaine [196] ... 

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