Sulfonyl hydrazine

With Af-acyl or Af-sulfonyl hydrazines as nucleophiles, Zincke salts serve as sources of iminopyridinium ylides and ylide precursors.Reaction of the nicotinamide-derived Zincke salt 8 with ethyl hydrazino urethane 42 provided salt 43, while the tosyl hydrazine gave ylide 44 (Scheme 8.4.14). ° Benzoyl hydrazines have also been used in reactions with Zincke salts under similar conditions.Af-amino-1,2,3,6-tetrahydropyridine derivatives such as 47 (Scheme 8.4.15), which showed antiinflammatory activity, are also accessible via this route, with borohydride reduction of the initially formed ylide 46. ... 

Lissamine rhodamine B sulfonyl hydrazine is a hydrazide derivative of sulforhodamine B that can spontaneously react with aldehyde- or ketone-containing molecules to form a covalent,... 

Lissamine rhodamine B sulfonyl hydrazine can react with aldehyde groups to form hydrazone linkages. 

Lissamine rhodamine B sulfonyl hydrazine is soluble in DMF. The reagent may be dissolved in this solvent as a concentrated stock solution before adding a small aliquot to an aqueous reaction medium. The compound itself and all solutions made with it should be protected from light to avoid decomposition of its fluorescent properties. 

Texas Red hydrazide is a derivative of Texas Red sulfonyl chloride made by reaction with hydrazine (Invitrogen). The result is a sulfonyl hydrazine group on the No. 5 carbon position of the lower-ring structure of sulforhodamine 101. The intense Texas Red fluorophore has a QY that is inherently higher than either the tetramethylrhodamine or Lissamine rhodamine B derivatives of the basic rhodamine molecule. Texas Red s luminescence is shifted maximally into the red region of the spectrum, and its emission peak only minimally overlaps with that of fluorescein. This makes derivatives of this fluorescent probe among the best choices of labels for use in double-staining techniques. 

Oxosteroids, oxo bile acids 5-Dimethylaminonaphthalene-l -sulfonyl hydrazine 82, 83... 

Lee has shown that the strnctnrally related sulfonyl hydrazine 19 provides a more active catalyst scaffold. Reactions proceed to completion in brine at 0 °C-rt in under 24 h, with respectable yields and enantioselectivities in many cases (71-99% yield 66-86% ee for endo 83-96% ee for exo) however, diastereoselectivities were once again poor (0.9 1-2.5 1 endo exo) (Scheme 5) [49]. 

Aldehydes, hydrazine I-Dimethylaminonaphthalene-5-sulfonyl hydrazine (dansyl hydrazine)... 

Lissamine rhodamine B sulfonyl hydrazine is a hydrazide derivative of sulforhodamine B that can spontaneously react with aldehyde- or ketone-containing molecules to form a covalent, hydrazone linkage (Fig. 217). It also can be used to label cytosine residues in DNA or RNA by use of the bisulfite activation procedure (Chapter 17, Section 2.1). The resulting fluorescent derivative exhibits an excitation maximum at a wavelength of 556 nm and a maximal emission wavelength of 580 nm when dissolved in methanol. In... 

Generalized protocols for the use of hydrazine-probes reactive toward aldehyde residues can be found in Section 1.1. These procedures are directed at the labeling of cell surface glycoproteins or glycoproteins in solution. Substitution of Lissamine rhodamine B sulfonyl hydrazine for the fluorescein-5 -thiosemicarbazide reagent described in that section can be done without difficulty. Some optimization may be... 

The hydrazide derivative can be used to modify aldehyde- or ketone-containing molecules, including cytosine residues using the bisulfite activation procedure described in Chapter 17, Section 2.1. The sulfonyl hydrazine group of Texas Red hydrazide reacts with aldehydes or ketones in target functional groups to form hy-drazone bonds (Fig. 218). Carbohydrates and glycoconjugates can be specifically labeled at the polysaccharide portion if the required aldehydes are first formed by periodate oxidation or another such method (Chapter 1, Section 4.4). 

A new efficient procedure has been proposed for the synthesis of 3-aryl-5-amino-l//-pyrazoles by reaction of a-chloro-/ -arylacrylonitriles with hydrazine hydrate <2004RJ01518>. Reaction of 2-(3,3-dicyano-2-propenylidene)-4,4,5,5-tetra-methyl-l,3-dioxolane 641 with hydrazine afforded 3-(2-hydroxy-l,l,2-trimethylpropoxy)pyrazole 642 (Equation 134) <2003RJ01016>. Treatment of ethyl 3,3-dicyano-2-methoxyacrylate with alkyl, aryl, heterocyclic, and sulfonyl hydrazines led to the synthesis of N-l-substituted 3-acyM-cyano-5-aminopyrazoles, which are versatile intermediates for the synthesis of many biologically active scaffolds <2006TL5797>. 2-Hydrazinothiazol-4(5//)-one reacted with a variety of cinnamonitrile derivatives and activated acrylonitriles to yield annelated pyrazolopyrano[2,3-rf thiazole <1998JCM730>. 

This extraordinary reaction converts a ketone into a vinyl-lithium 32. First an aryl sulfonyl hydra-zone 31 is made by the obvious condensation with the aryl sulfonyl hydrazine 30. Treatment with two equivalents of butyl-lithium gives the vinyl-lithium.5... 

Carbene generation Alumina—Potassium hydroxide. Bis(tribromomethyl)mercury. Bis (trimethylsilyldichloromethyl)mercury. Bromotrifluoromethane. n-Butyllithium. Copper (II) acetylacetonate. Diazoacetaldehyde. Di-n-chloro-x-allyldipalladium. Dichloromethyl 2-chloroethyl ether. Dicyanodiazomethane. sym-Difluorotetrachloroacetone. Ethylene oxide. Methyl dichlorofluoroacetate. Methyllithium. Phenyl (trichloromethyl)mercury. Sodium chlorodifluoroacetate. Sodium trichloroacetate. Thallous ethoxide. / -Toluene-sulfonyl-hydrazine. 

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