1576-39-2Relevant articles and documents
Selective Deprotection of N -Tosyl Alkoxyamines Using Bistrifluoromethane Sulfonimide: Formation of Oxime Ethers
Azizi, Mohamed Salah,Cossy, Janine
supporting information, p. 2417 - 2421 (2018/11/23)
The detosylation of N -tosyl alkoxyamines was realized by treatment with benzaldehyde and bistrifluoromethane sulfonimide as the catalyst to afford the corresponding oxime ethers. The reaction is chemoselective as N -tosyl amines are not deprotected. A me
Sulfonamide synthesis via oxyma-O-sulfonates - Compatibility to acid sensitive groups and solid-phase peptide synthesis
Palakurthy, Nani Babu,Dev, Dharm,Rana, Shubhasmin,Nadimpally, Krishna Chaitanya,Mandal, Bhubaneswar
, p. 2627 - 2633 (2013/06/04)
A milder and more efficient procedure for the synthesis of sulfonamides by activating sulfonic acid groups as the corresponding sulfonate esters of ethyl 2-cyano-2-(hydroxyimino)acetate (Oxyma) is reported. This method is greener than all other existing protocols for the purpose. Other important advantages lie in (a) its applicability to less nucleophilic anilines under ambient and milder conditions and (b) its compatibility with solid phase peptide synthesis and acid-labile groups such as trityl (Trt) and tBu, which empowers the solid phase synthesis of sulfonamides of various peptides. To illustrate this, the syntheses of three sulfonamide derivatives of the peptide GAILG-NH2, which is relevant in the context of drug design against type 2 diabetes, are demonstrated by using Fmoc-based solid-phase peptide synthesis (SPPS). The activation of sulfonic acids as their corresponding O-sulfonate esters facilitates sulfonamide synthesis, which can be applied to those substrates that possess acid-labile functional groups and is compatible with solid phase synthesis. Copyright
O-Substituted N-oxy arylsulfinamides and sulfonamides in Michael reactions
Bonifacio, Vasco D. B.,Kumar, Rakesh P.,Prabhakar, Sundaresan,Lobo, Ana M.
experimental part, p. 266 - 276 (2011/11/06)
O-Substituted N-oxy arylsulfinamides and sulfonamides undergo fast aza-Michael reaction in the presence of base and electron-deficient α,β-unsaturated olefins under mild conditions. With N-silyloxy benzenesulfinamides, no aza-Michael product is observed and a hetero aza-Brook type rearrangement takes place induced by the base. Room temperature N-desulfinylation of N-benzyloxybenzenesulfinamide is achieved using BF 3.Et2O. N-Alkoxy arylsulfonamides aza-Michael adducts are found to be generally highly stable under strongly acidic and basic conditions.
A straightforward route to piloty's acid derivatives: A class of potential nitroxyl-generating prodrugs
Porcheddu, Andrea,De Luca, Lidia,Giacomelli, Giampaolo
experimental part, p. 2149 - 2153 (2011/03/20)
A series of Piloty's acid derivatives were easily prepared under mild and neutral conditions. The ease of isolation of the final product offers a marked advantage over well-known procedures. This methodology is particularly attractive as it cleanly provided low molecular weight aliphatic sulfohydroxamic acids, which are very interesting for their tendency to generate HNO under physiological conditions. Georg Thieme Verlag Stuttgart.
Synthesis of cyclic hydroxamic acids through -NOH insertion of ketones
Banerjee, Ranjan,Bruce King
supporting information; experimental part, p. 4580 - 4583 (2009/12/09)
Treatment of cyclobutanone or cyclopentanone with N- hydroxybenzenesulfonamide under basic conditions yields the ring-expanded cyclic hydroxamic acid in 18-69% yield. Reactions of substituted cyclobutanones give ring expanded products where the -NOH group regio- and stereoselectively inserts to the more substituted position. This expansion likely proceeds through a mechanism that includes addition of the N-anion of N-hydroxybenzenesulfonamide to the ketone and a C-nitroso intermediate that rearranges to the final product.
Preparation and Reactions of N-Phenacyl-N-tosylhydroxylamines and -hydrazines
Wessig, Pablo,Henning, Hans-Georg
, p. 983 - 986 (2007/10/02)
O-Alkyl-N-phenacyl-N-tosylhydroxylamines 3 were prepared in two steps from O-alkylhydroxylamines 1.In the presence of a base the N-tosylhydroxylamines 3 undergo rearrangement and cleavage to N-tosylphenacylamine (5) and aldehydes 6.N-Alkyl-N'-phenacyl-N,N'-ditosylhydrazines 12 were obtained by stepwise treating of N,N'-ditosylhydrazine with alkyl halide and phenacyl bromide/potassium tert-butoxide/DMF
Reactions of N-Acyl-O-arylhydroxylamines: Part IV - Preparation of Some N-Arylsulphonyl-O-arylhydroxylamines
Singha, A. S.,Misra, B. N.
, p. 361 - 363 (2007/10/02)
A number of N-arylsulphonyl-O-alkylhydroxylamines (III) have been prepared by condensing appropriate alkoxyamines with arylsulphonyl chlorides in the presence of a base.The alkoxyamines have been obtained from the corresponding alkoxyamine hydrochlorides or hydrobromides (II) which in turn have been prepared by the hydrolysis of appropriate N-benzoyl-O-alkylhydroxylamines (I) with ethanolic hydrogen chloride or hydrogen bromide.The structure assignments of III are based on elemental analyses, chemical reaction and spectral (IR, PMR) data.
