N-Lost derivatives

These polymers are essentially less toxic (factor of 2-10 at LDs0) and partially very much longer active than free sarkolysin. An increase in activity, however, is not attained. Here, the mode of action is, however, not clear because bifunctional chloro-alkylamine derivatives ( N-Lost derivatives) seem to be necessary to show some activity. Possibly in this case the alkylpyridinium compound decomposes into a derivative of ethylene or the chloroethyl group is formed again so that a second reactive group is formed besides the chloroethyl residue which is still present. 

Analogous to a N-Lost derivative, introduced in Germany, the Endoxane , a polymeric substance [31] has also been synthesized (99). 

The carboxamide moiety was then examined, preparing several 2,4-dichlorophenoxy compounds in solution (9.37-9.43, Fig. 9.20). Replacement of the primary amide with small N-nucleophile-derived groups (9.41-9.43) maintained activity, as did the methyl ester-substituted 9.39 while the free acid 9.38, the deletion compiound 9.37, and more complex secondary amide analogues lost inhibitory activity. The hydroxamate function significantly increased the solubihty profile of 9.43 thus it was considered relevant for the optimization of the chemical series (Fig. 9.20). 

Tertiary aliphatic amines (and, to an extent, tertiary aromatic amines, too, particularly if the para position is blocked) react with nitrous acid to yield an N-nitroso derivative of a secondary amine the group that is lost from nitrogen appears as an aldehyde or ketone. Although this reaction is not really understood, it too seems to involve the initial attack by NO on nitrogen. 

The ammonium salt which results from the transformation of sulfuryl amide can be converted to a silver salt, AgNSO ELO, by silver nitrate (64) and this readily gives AgNS02. The silver salt with methyl iodide yields the N-methyl derivative (LXXI) (61). Since molecular weight determinations show the methyl derivative to be a trimer, it may also be assumed that the salts, and particularly that of silver, are also trimeric. Attempts to isolate the hydrogen compound (LXIX) have so far failed, but Heinze and Meuwsen (64) have prepared many salts of (LXIX). They also were able to show that when the silver salt was decomposed with an equivalent quantity of hydrochloric acid a tribasic acid resulted which was to some extent stable in water. It readily lost two protons, but one proton was split off only with difficulty. The ion (LXX) clearly has a high stability. The dipyridinium salt of the trimeric sulfimide, which is derived from the ion (LXX), can be obtained (la) in a yield of 70% by reaction of amido-sulfuric acid chloride with pyridine at 20° ... 

There are large differences in reactivity among the various carboxylic acid derivatives, such as amides, esters, and acyl chlorides. One important factor is the resonance stabilization provided by the heteroatom. This decreases in the order N > O > Cl. Electron donation reduces the electrophilicity of the carbonyl group, and the corresponding stabilization is lost in the tetrahedral intermediate. 

Another example of this is the loss of acetic acid when delphinine is heated in hydrogen at 200-215°. Just as aconitine is so converted into pyraconitine so delphinine yields pyrodelphinine, C3 H4 0,N, m.p. 208-212°, and similarly a-oxodelphinine, C33H430j qN, under like treatment loses acetic acid and yields pyro-a-oxodelphinine, C3 H3gOgN, which crystallises from methyl alcohol in needles, m.p. 248-250°, after sintering at 238°. This, on hydrogenation, forms a hexahydro-derivative, m.p. 183-5°, presumably by saturation of the benzoyl radical, which therefore leaves unexplained the mechanism by which acetic acid is lost in this pyrolytic reaction (c/. pyropseudaconitine, p. 683). 

Reaction of Na[FcC(NCy)2l with CpFe(CO)2l afforded the carbamoyl derivative CpFe(CO)[FcC(NCy)N(Cy)C(0)] (Scheme 136). Although not thermally labile, a CO ligand is readily lost on UV irradiation to give the amidinate derivative CpFe(CO)[FcC(NCy)2]- The addition of CO (SOpsig) to a solution of... 

When excess amounts of the HHT of phenyl glycinate 42 were used with diphenyl phosphite, the preferred product was the novel cyclic derivative 45 (2). Presumably, ring-opening of the HHT produced intermediate 43 first, which lost an equivalent of glycinate formaldimine to give 44. The proximity of the activated phenyl carboxylate ester to the N-H in 44 presumably promoted intramolecular cyclization to 45 with loss of phenol (2). 

C SOC retained SOClost SOC sSOC SOC SOC n Associated 813C value Amount of organic carbon lost Rayleigh fractionation constant of the SOC Soil organic carbon derived from com stover Total corn-derived carbon in the residue returned treatment Com derived from unharvested material in the stover harvested treatment... 

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