1.3.5- Triazine structure

Works on the oxidation of uric acid has unequivocally established the triazine structure > ° (9) of oxonic acid. This is further confirmed by the straightforward synthesis described by Piskala and Gut. ° The reaction of biuret (11) with potassium ethyloxalate yielded a potassium salt (24), that with ethyl oxamate, the amide of oxonic acid (25). Both these compounds were converted to 5-azauracil. An analogous reaction with diethyloxalate which should produce an ester of oxonic acid resulted in a mixture of urethane and parabanic acid, however. 

Hence, by this pathway the formation of allantoin is not at variance with the triazine structure of oxonic acid. 

Trigard 75 WP is a new insecticide with a unique mode of action and a unique triazine structure. It is a solid formulated as a wettable powder and is packaged in water-soluble bags. The active ingredient in Trigard has the common name cyromazine. Cyromazine is a triazine, but, unlike the well-known triazine herbicides, this compound has insecticidal properties and no herbicidal activity. Cyromazine has low mammalian toxicity and low vapor pressure. It is hydrophilic, so dermal penetration is expected to be... 

The kinetics of reaction of DABCO (7.66) and nicotinic acid (7.67 R = COOH) with the aminochlorotriazine dye Cl Reactive Red 3 (7.2) were studied under neutral conditions at temperatures in the range 100-130 °C. Quaternisation by DABCO was much more rapid than by nicotinic acid under these conditions. Neutral exhaust dyeing tests at 130 °C using the bis(aminochlorotriazine) analogue Cl Reactive Red 120 (7.48 X = Cl) with the two catalysts confirmed these trends, in that the degree of fixation was greatly increased by DABCO but nicotinic acid showed no appreciable catalytic effect [60]. This difference may be attributable to steric strain of the C-N+ bond in the quaternised triazine structure by the non-planar DABCO substituent. 

The chemical name for research department explosive (RDX) is cyclotrimethylene trinitramine or 1,3,5-trinitrohexahydro-sym-triazine [Structure (2.14)]. Because of... 

Comparison of cyclic compounds 38 and 39 shown in equation 88 via correlated MP2/6-31G //HF/6-31G calculations indicated that the cyclic trisilylene 38 is more stable than the trisila-s-triazine structure 39 by 30 kcalmol-1 at the CCSD/6-31GV/MP2/ 6-31G ... 

Figure 8.1 Examples of herbicides and herbicide classes containing some compounds that inhibit photosynthesis with a mode of action like that of the triazines. Structures within the boxes are essential elements common to all classical inhibitors of photosynthesis II at the QB site. Some phenolic compounds also inhibit in a similar way.

Table 27.1 Triazine structures, toxicological endpoints and safety factors...

Yadav and Kapoor [13] synthesized the acyclic C-nucleosides (xii) incorporating the thiazole-s-triazine structure as a nucleobase following a three-component, one-pot reaction under solvent free condition and microwave irradiation. 

T-electron delocalisation in the Pc-layers. On the other side a reaction between TCB and Cu(II)-acetylacetonate formed a polymer showing broad absorptions in the IR-spectra (Fig. 6, C). Also the UVA IS-spectra have an very intensive ateorption beginning at 500 nm and increasing with shorter wave length which is typical for polynitrile like (97) (Fig. 7, C). Pc-units are identified only at small absorptions at 735 nm. There is no indication of triazine structure elements (92) having absorption lines at 1610,1540,1450 and 1370 cm". ... 

The triazine herbicides are based on an s-triazine structure containing two amino groups. Atrazine, simazine and terbutryne present an absorption peak around 225 nm (Fig. 55), whereas hexazinone (Fig. 56) has an absorption maximum at 248 nm. 

Similar polyols with triazinic structure are obtained by using cyanuric acid condensates. Cyanuric acid is a product of urea thermal decomposition or the product of hydrolysis of melamine or of cyanuryl chloride [40]. 

By the reaction of cyanuric acid with formaldehyde or by Mannich reaction with formaldehyde and diethanolamine interesting polyolic starters with heteroxyxlic triazinic structure are formed [31,41] ... 

By propoxylation of the resulting polyols (trimethylolisocyanurate and the Mannich base (15.44), in the presence of a tertiary amine as catalyst (for example dimethylaminoethanol) new heterocyclic polyols for rigid PU foams with a triazinic structure are obtained (reactions 15.45 and 15.46). 

All the triazinic polyols discussed here, have a high thermostable triazinic structure and a high nitrogen content, which gives inherently flame retardant, rigid PU foams [24]. 

Triazines are well-known compounds and a wide variety of synthetic methods for their preparation exist. Since the first report of the synthesis of a compound with a 1,2,4-triazine structure in 1889 by Bischler,1 almost 10,000 papers have been published covering all aspects, e.g. chemical, physical, spectroscopic, analytical, biological, biochemical, agrochemical, environmental etc., of 1,2,4-triazines, their benzo derivatives and heterocyclic condensed derivatives. 

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