Triazenes diethyl

Sulfonyl azides are exceptional in that they do not normally give triazoles with activated methylene compounds nucleophilic attack by the carbanion is usually followed by loss of the sulfonamide anion, giving a diazo compound as the product. Possible mechanisms for the reaction are illustrated (Scheme 8) for diethyl malonate. Attack of the carbanion on the terminus of the azide gives the anion of the linear triazene (1). 

Triazene 1(1.3-Diethyl-5-trifluoro-methyl-bcn7imidazolitim-2-yl)-3-(1.3-diethyl-5-trifluoromethyl-2 3-di hydro-bell/imid izol-2-yliden)- EI4b/1 729 (2-Nj-subst.-Benzimidazolium A)... 

Method C), in the case of silylated amides (R, R" = SiXs) in diethyl ether at -20°C, leads to disilylaryltriazenes (9) (7) in good yields (for individual compounds, cf. Table I). The latter compounds, formed according to Eq. (8), exist in the cis as well as the trans configuration. In fact, the formation of cu-triazene is favored with decreasing reaction temperature, whereas tram-triazene formation is favored with increasing reaction temperature. ... 

SYNS DIETHYL-TRIAZENE N,N -DIETHYL-TRIAZENE 1,3-DIETH LTRIAZENE 1,3-DIETHYL-1-TRIAZENE 1,3-DIETHYLTRIAZINE 1-TRIAZENE, 1,3-DIETHYL-(9CI)... 

DIETHYL-l-(m-PYRIDYL)TRIAZENE see DJYOOO DIETHYL PYROCARBONATE see DIZlOO DIETHYL PYROCARBONIC ACID see DIZlOO... 

The high anti-tumour selectivity of the triazenes and their broad spectrum of action requires further investigation since it may eventually enable the design of agents for clinical use which maintain their anti-tumour specificity but do not break down into products which are toxic but not tumour inhibitory. The role of formaldehyde produced by the active dimethyl derivatives but not by the inactive diethyl analogues, may be important. It has also recently been proposed that toxic products formed by triazenes may be neutralised by factors in the cytoplasm of normal tissues but not in sensitive tumour cells77. ... 

The application of a triazene motif to the development of a photolabile linker was reported by Enders in 2004 [63]. The reaction of a secondary amine with polymer-bound diazonium salt 45 produced the triazene moiety 46. It was stable to a wide range of non-acidic conditions, suitable for other organic reactions. Photocleavage was carried out with 355 nm UV laser irradiation (3co Nd-YAG) in methanol-diethyl ether (Scheme 17.22). 

The reaction of (chloroformyl)ketenes with triazenes in diethyl ether affords mesoionic 1,2,3-triazines in yields between 65 and 90%.352... 

Standard methods involving glycosyl halide or ester derivatives in reaction with protected heterocycles have been applied to the synthesis of various glycosyl derivatives of 5-fluoro-uracil and -cytosine, a number of nitro-imidazoles and -pyrazoles, thiadiazines and oxadiazolo-thiadiazines, and 5-methylthio derivatives of -uracil, -4-thiouracil, and -cytosine,/3-D-ribofuranosyl derivatives of 2-thio-6-azauracil, diethyl 4-hydroxypyrazole-3,5-dicarboxylate, 5-acetyl-uraeil, 2,4- and 2,5-thiazolidinediones, 4-thiomethyl-2-azapurine, 2-hydroxypurine, 3-deaza-adenine-8- C, l-deaza-8-azaguanine, imidazo-(l,2- )l,3,5-triazenes, e.g., (5), //n-benzo-guanosine, -inosine, and -xanthosine (6), and a derivative of lV-2-(i3-D-ribopyranosyl)benzotriazoie. Likewise 2-0-... 

Chlorosulfonyl)-2-sulfophenyl]-3,6-bis(diethylamino)xanthylium, C-00261 >2,6-Dibromo-4-(chloroimino)-2,5-cyclohexadien-l-one, D-00180 >2,6-Dichloro-4-(chloroimino)-2,5-cyclohexadien-l-one, D-00257 3,3- Diethyl-1 -(9Ff-fluoren-2-yl)-1 -triazene, D-00347... 

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