Triazine activation method

FIGURE 3.13 Schematic representation of (a) cyanogen bromide reaction, (b) cyclic rranr-2,3-carbonate activation method, (c) triazine activation method, and (d) carbonylation reaction. 

This review deals with methods for the synthesis of 1,2,4-triazine mono-lV-oxides and their reactivity. The interest in 1,2,4-tiiazines is due to their incorporation in many natural and artificial compounds, their biological activity, and other useful properties. 

Applicators, mixers, loaders, and others who mix, spray, or apply pesticides to crops face potential dermal and/or inhalation exposure when handling bulk quantities of the formulated active ingredients. Although the exposure periods are short and occur only a few times annually, an estimate of this exposure can be obtained by quantifying the excreted polar urinary metabolites. Atrazine is the most studied triazine for potential human exposure purposes, and, therefore, most of the reported methods address the determination of atrazine or atrazine and its metabolites in urine. To a lesser extent, methods are also reported for the analysis of atrazine in blood plasma and serum. 

Melarsen (211) is active against both early and late stages of African trypanosomiasis. The antimony derivative (212) is used similarly (B-61MI22000, p. 715). 2,4,6-Tripyridyl-l,3,5-triazine forms a purple bis(triazinyl) complex with iron(III) ions which provides a spec-trophotometric method for estimating iron in wines (59MI22001). 

Compounds with the same mode of action interact with the same binding site on the protein. Triazines and ureas, as well as the other compounds listed in Figure 8.1, displace plastoquinone QB. Therefore, they also displace each other from the target site in PS II, and their inhibitory potency can be evaluated by the procedure introduced by Tischer and Strotmann (1977). This is experimentally followed with a radioactive derivative in which a 14C labeled triazine is bound to the target. The radioactivity will be diluted out of this site by an unlabeled compound of similar potency and mode of action. This method does not require measuring photosynthetic activity, but does require a structurally and functionally intact PS II because binding efficiency is easily lost by improper handling of the membrane. 

The usual synthetic method for the production of this system is the reaction of a 5,6-diamino-triazine with an organic acid equivalent. In Scheme 11 the activated nitrile (115) is displaced by benzamidine to give the intermediate (116) which is cyclized by base forming the imidazotriazine... 

The wide ranging biological activity associated with triazine derivatives, both naturally occurring and synthetic ensures that the synthesis of this important ring system remains a topic of current interest. Various methods for the preparation of these compounds have been reported. 

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