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PubMed2003

Synthesis, structural determination and dynamic behavior of 2-chloro-4,6-bis(pyrazolylamino)-1,3,5-triazines.

A series of 2-chloro-4,6-bis(pyrazolylamino)-1,3,5-triazines with applications in crystal engineering have been prepared. At low temperature, the presence of two or three isomers has been detected and these assigned to 4,6-diamino-1,3,5-triazine structures on the basis of comparison with model compounds. 2D-Exchange spectroscopy studies in various solvents and at different temperatures have been used to determine the equilibrium constants and the activation free energies of the restricted rotation about the amino-triazine bond. A plot of the activation free energy versus temperature showed a good linear correlation and confirmed that the same process is present in all of the compounds under investigation. Comparison with model compounds also confirmed both the occurrence of the restricted rotation and the 4,6-diamino-1,3,5-triazine tautomerism for triazines 1-4 in solution. The structure of compound 1 has been determined in the solid state by X-ray crystallography and consists ofa 4,6-diamino- 1,3,5-triazine structure stabilized by intra and intermolecular hydrogen bonds.

Crystallography, X-Ray↗

PubMed2000

Role of prolactin in chloro-S-triazine rat mammary tumorigenesis.

Chloro-S-triazine herbicides [cyanazine (CZ), atrazine (AZ), simazine (SZ)] increase mammary tumors in Crl:CD BR rats but not in F-344 rats or in mice. A nongenotoxic mechanism was investigated since the chloro-S-triazines are negative in short-term tests for genotoxicity. An in vivo battery was used to assess the chloro-S-triazines for estrogenic activity or for their ability to increase prolactin (PRL) levels, both of which play important roles in enhancing mammary gland tumorigenesis in rodents. Ovariectomized (OVX) female rats were treated with AZ, CZ, SZ, or three CZ metabolites for 4 days via intraperitoneal injection. The pattern of responses between the chloro-S-triazines and four controls (estradiol, estriol, haloperidol, reserpine) was compared. For the 6 end-points examined, the responses from rats treated with AZ, CZ, SZ, and the metabolites of CZ most closely matched the responses from the reserpine-treated rats (a PRL rather than estrogenic mechanism). In addition, AZ, CZ, and SZ were tested in several other in vitro models (estrogen/biogenic amine receptor competition assays and a yeast-expressed human estrogen receptor transcription assay) as well as an in vivo 24 h time-course experiment to characterize the CZ-induced increases in PRL levels. AZ, CZ, and SZ are not estrogen receptor (ER) activating compounds based on yeast transactivation and receptor competition data. CZ and AZ demonstrated marginal competition (at mM levels) to the D and alpha2 adrenergic receptors. Ligands to the D2 receptor, but not the alpha2 adrenergic receptor, are known to induce mammary tumors. CZ was also found to produce elevated PRL levels in a time-course similar to that seen with reserpine and haloperidol. Overall, the pattern of responses obtained with the chloro-S-triazines most closely matched the responses observed for reserpine. Taken together, these data suggest chloro-S-triazine-induced mammary tumors in rats are mediated through a PRL mechanism, which is thought to be of low relevance to humans.

Adrenergic Uptake Inhibitors↗

PubMed1992

The binding of triazine herbicides to the photosynthetic reaction center of Rhodopseudomonas viridis. Energy minimization studies.

The binding of six herbicides of the triazine family to the photosynthetic reaction center of Rhodopseudomonas viridis was investigated with energy-minimization techniques, in order to correlate experimental with calculated data. The inhibitors were modeled in the active site according to the X-ray structure analysis of the complex formed between the triazine terbutryn (2-ethylamino-4-t-butylamino-6-methylthio-s-triazine) and the reaction center of R. viridis [Michel, H., Epp. O. & Deisenhofer, J. (1986) EMBO J. 5, 2445-2451]. 40 different energy minimizations were carried out with varying cutoff radii, partial charges on inhibitor atoms and dielectric constants, i.e. 10 different combinations of these were tested. The impact of these parameters on the calculated binding and interaction energy was either examined for all protein/triazine complexes or, in the case of the dielectric constant, a smaller sample was used. The calculated energies are dominated by van der Waals interactions, which change by up to 20% when extending the cutoff radius from 0.8 nm to 1.5 nm. The use of uniform or distance-dependent dielectric constant or partial charges on the inhibitor atoms does not severely influence the resulting structures, but shows a great impact on the calculated energies. In the two groups of triazines, each containing three inhibitors with methoxy or methylthio substituents, correlations of biological and calculated data were found quite often, but only once with all six triazines. The energy-minimized structures were compared and analysed. A third hydrogen bond, not seen in the X-ray analysis of the reaction center/tertubryn complex, was found between the t-butylamino moiety of terbutryn (and equivalent moieties in the other triazines) and the carbonyl oxygen of TyrL222.

Chemical Phenomena↗

PubMed1999

Gene sequence and properties of an s-triazine ring-cleavage enzyme from Pseudomonas sp. strain NRRLB-12227.

Pesticides based on the s-triazine ring structure are widely used in cultivation of food crops. Cleavage of the s-triazine ring is an important step in the mineralization of s-triazine compounds and hence in their complete removal from the environment. Cyanuric acid amidohydrolase cleaves cyanuric acid (2,4,6-trihydroxy-s-triazine), which yields carbon dioxide and biuret; the biuret is subject to further metabolism, which yields CO(2) and ammonia. The trzD gene encoding cyanuric acid amidohydrolase was cloned into pMMB277 from Pseudomonas sp. strain NRRLB-12227, a strain that is capable of utilizing s-triazines as nitrogen sources. Hydrolysis of cyanuric acid was detected in crude extracts of Escherichia coli containing the cloned gene by monitoring the disappearance of cyanuric acid and the appearance of biuret by high-performance liquid chromatography (HPLC). DEAE and hydrophobic interaction HPLC were used to purify cyanuric acid amidohydrolase to homogeneity, and a spectrophotometric assay for the purified enzyme was developed. The purified enzyme had an apparent K(m) of 0.05 mM for cyanuric acid at pH 8.0. The enzyme did not cleave any other s-triazine or hydroxypyrimidine compound, although barbituric acid (2,4, 6-trihydroxypyrimidine) was found to be a strong competitive inhibitor. Neither the nucleotide sequence of trzD nor the amino acid sequence of the gene product exhibited a significant level of similarity to any known gene or protein.

Amidohydrolases↗

PubMed2005

NDELA and nickel modulation of triazine disposition in skin.

Cutting fluids can become contaminated with metals (e.g., nickel, Ni) and nitrosamines (e.g., N-nitrosodiethanolamine, NDELA) and there is concern that these classes of contaminants can modulate dermal disposition and ultimately the toxicity of cutting fluid additives, such as irritant biocides (e.g., triazine). Biocides are added to these formulations to prevent bacterial degradation of commercial cutting fluids. The purpose of this study was to assess the dermal absorption and skin deposition of 14C-triazine when topically applied to porcine skin in an in vitro flow-through diffusion cell system as aqueous soluble oil (mineral oil, MO) or aqueous synthetic (polyethylene glycol, PEG) mixtures. 14C-Triazine mixtures were formulated with NDELA and/or Ni, or with a combination of three additional cutting fluid additives; namely, 5% linear alkylbenzene sulfonate (LAS), 5% triethanolamine (TEA) and 5% sulfurized ricinoleic acid. Neither Ni nor NDELA was absorbed during these 8-h studies. However, 14C-triazine absorption ranged from 2.72 to 3.29% dose in MO and 2.29-2.88% dose in PEG with significantly greater triazine absorption in MO than PEG when all additives and contaminates were present. The difference between these two diluents was most pronounced when NDELA and/or Ni were present in cutting fluids. These contaminants also enhanced triazine deposition on the skin surface and skin tissues especially with PEG-based mixtures. In essence, the dermal disposition of irritant biocides could be dependent on whether the worker is exposed to a soluble oil or synthetic fluid when these contaminants are present. Workers should therefore not only be concerned about dermatotoxicity of these contaminants, but also the modulated dermal disposition of cutting fluid additives when these contaminants are present in cutting fluid formulations.

Alkanesulfonic Acids↗

PubMed1997

In vitro cytotoxicity of imidazolyl-1,3,5-triazine derivatives.

We examined in vitro cytotoxic activity of imidazolyl-1,3,5-triazine derivatives using human breast cancer cell lines (MCF-7, R-27, T-47D and ZR-75-1) and murine leukemia cell line (P388). The percentage of viable cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazorium bromide (MTT) assay. Hexamethylmelamine (HMM), a 1,3,5-triazine derivative has previously been recognized as an antitumor agent effective against lung, ovarian and breast cancer, but failed to show a significant cytotoxic activity in the present study. In contrast, four imidazolyl-1,3,5-triazine derivatives, 2-(1-imidazolyl)-4,6-bis(morpholino)-1,3,5-triazine, 2-(1-imidazolyl)-4-morpholino-6-(3-thiazolidinyl)-1,3,5-triazine, 2-(4-cyano-4-phenylpiperidino)-4-(1-imidazolyl)-6-morpholino-1,3,5-triaz ine and 2-(1-imidazolyl)-4-(N-methyl-N-phenylamino)-6-morpholino-1,3,5-triazine showed cytotoxic activity for most cell lines, which was significantly greater than the activity of hydroxymethylpentamethylmelamine (HMPMM), a major metabolite of HMM.

Altretamine↗

PubMed2005

Aging of triazine amine in soils demonstrated through sorption, desorption, and bioavailability measurements.

The aging of triazine amine in soil was studied during a time course of 119 d by measuring bioavailability in terms of mineralization after inoculation of the triazine amine-degrading bacterium Rhodococcus erythropolis TA57. The bioavailability was measured in four soil samples: A-, B-, and C-horizons from an agricultural soil profile and in a peat soil. The sorption of triazine amine in the soil samples was quantified during the period of aging in terms of sorption distribution coefficients (Kd) and desorption distribution coefficients (Kd,des). Measures of bioavailability and triazine amine concentration in the nonavailable fraction showed effects of aging in the soils that were rich in organic matter. The triazine amine bioavailability declined significantly during the aging period in soils containing greater than 2% organic carbon, whereas the B- and C-horizons showed no signs of aging, in agreement with their low content of organic material. Corresponding to this, desorption decreased significantly in the A-horizon but, surprisingly, not in the peat soil. Analyses by thin-layer chromatography indicated an association of aqueous triazine amine and dissolved organic matter in the peat soil. This gives an explanation for both the significant decrease in bioavailability and the noncorresponding stability of the nonavailable (i.e., nondesorbed) fraction.

Adsorption↗

PubMed1969

Chemosterilization of Culex pipiens fatigans Wiedemann by exposure of aquatic stages. 2. Sterilization potential of certain phosphoramides and s-triazines.

Many aziridinyl compounds are known to induce high sterility in Culex pipiens fatigans Wiedemann, but as the practical application of these chemosterilants is quite hazardous, compounds such as phosphoramides and s-triazines have been tried against this species. These compounds are relatively less reactive, thermally more stable and less toxic to mammals. The phosphoramides included hempa, N,N,N',N'-tetramethyl-P-piperidino-phosphonic diamide (ENT-51007) and a compound, ENT-60210, whose structure is not known to the authors. The s-triazines employed were hemel, 2,4-diamino-6-morpholino-s-triazine hydrochloride (ENT-51143), 2-amino-4,6-bis (dimethylamino)-s-triazine hydrochloride (ENT-51146), and a compound ENT-60433, whose structure is not known to the authors.The triazines were more toxic than the phosphoramides in both larval and pupal treatments. Among the phosphoramides, hempa and ENT-51007 were quite promising for larval treatment and resulted in 80% and 83% control of reproduction respectively at non-toxic doses. Hempa at a toxic dose induced complete sterility. ENT-60210 was least toxic and least effective. Among the triazines, hexa-substituted hemel was better than tetra-substituted ENT-51146 and cyclic-substituted ENT-51143 in inducing sterility. ENT-51143 was most toxic and least effective. For larval treatment, hempa was better than hemel in inducing sterility while for pupal treatment the latter was better than hempa. Both the compounds produced more sterility in treated females than in treated males. Oviposition was significantly lowered in treated females.

Amides↗

PubMed2005

Highly blue luminescent triazine-amine conjugated oligomers.

[Reaction: see text]. The novel synthetic strategy and optical properties of highly fluorescent, triazine-amine conjugated oligomers are described herein. Under basic conditions, aromatic dinitrile compounds, NC-C6H4-X-C6H4-CN (X = NMe, O, CH2), underwent cyclic trimerization of the cyano groups at both ends to give a series of triazine-containing oligomers. The oligomers can be expressed as (2n + 1) mer, where n represents the number of triazine rings in the oligomer. The absorption maximum of an amine-conjugated trimer (X = NMe, n = 1) was outstandingly red-shifted as compared with those of the other trimers (X = CH2, O). In acidic media, the amine-conjugated trimer showed two-step bathochromic shifts caused by protonation. The absorption maxima of the amine-conjugated (2n + 1) mers (X = NMe, n = 1-4) did not depend on n; instead, shoulder peaks appeared in the long-wavelength region when n 2. The oligomers involving alternate conjugation of triazines and NMe groups through phenylene groups showed strong fluorescence in chloroform. In particular, the pentamer was the most efficient blue emitter (PhiF = 0.82). The other triazine-containing oligomers (X = CH2, O) did not show fluorescence at all. Therefore, it is concluded that the emission properties are due to the strong electron-donating and accepting abilities of the NMe and triazine moieties, respectively.

Journal Article↗

PubMed1983

Comparison of Photosynthetic Performance in Triazine-Resistant and Susceptible Biotypes of Amaranthus hybridus.

The rate of CO(2) reduction in the S-triazine-resistant biotype of smooth pigweed (Amaranthus hybridus L.) was lower at all levels of irradiance than the rate of CO(2) reduction in the susceptible biotype. The intent of this study was to determine whether or not the lower rates of CO(2) reduction are a direct consequence of the same factors which confer triazine resistance. The quantum yield of CO(2) reduction was 23 +/- 2% lower in the resistant biotype of pigweed and the resistant biotype of pigweed had about 25% fewer active photosystem II centers on both a chlorophyll and leaf area basis. This quantum inefficiency of the resistant biotype can be accounted for by a decrease in the equilibrium constant between the primary and secondary quinone acceptors of the photosystem II reaction centers which in turn would lead to a higher average level of reduced primary quinone acceptor in the resistant biotype. Thus, the photosystem II quantum inefficiency of the resistant biotype appears to be a direct consequence of those factors responsible for triazine resistance but a caveat to this conclusion is discussed. The effects of the quantum inefficiency of photosystem II on CO(2) reduction should be overcome at high light and therefore cannot account for the lower light-saturated rate of CO(2) reduction in the resistant biotype. Chloroplast lamellar membranes isolated from both triazine-resistant and triazine-susceptible pigweed support equivalent rates of whole chain electron transfer and these rates are sufficient to account for the rate of light-saturated CO(2) reduction. This observation shows that the slower transfer of electrons from the primary to the secondary quinone acceptor of photosystem II, a trait which is characteristic of the resistant biotype, is nevertheless still more rapid than subsequent reactions of photosynthetic CO(2) reduction. Thus, it appears that the lower rate of light-saturated CO(2) reduction of the resistant biotype is not limited by electron transfer capacity and therefore is not a direct consequence of those factors which confer triazine resistance.

Journal Article↗

PubMed1990

Triazine Resistance in Senecio vulgaris Parental and Nearly Isonuclear Backcrossed Biotypes Is Correlated with Reduced Productivity.

Isonuclear triazine-susceptible and triazine-resistant Senecio vulgaris L. biotypes were developed by making reciprocal crosses between susceptible and resistant biotypes to obtain F(1) hybrids and backcrossing the hybrids to the appropriate pollen parent. The electrophoretic isozyme patterns of the enzyme aconitase obtained from leaf extracts of triazine-susceptible parental (S) and backcrossed (SxR(BC6)) biotypes, and triazine-resistant parental (R) and backcrossed (RxS(BC6)) biotypes verified that the biotypes had the expected nuclear genomes. Atrazine inhibition of chloroplast whole chain electron transport from water to methyl viologen was measured to verify susceptibility or resistance to triazine herbicides. The photosynthetic rate and biomass accumulation of greenhouse grown susceptible and resistant S. vulgaris biotypes were measured 28, 35, 42, 50, 57, and 64 days after planting to determine the effect of altered chloroplast function. S and SxR(BC6) biotypes had CO(2) assimilation rates of 16.2 and 16.6 micromoles CO(2) per square meter per second, respectively, and I(50) values (herbicide concentration producing 50% inhibition) of about 0.49 micromolar atrazine. The corresponding values for the R and RxS(BC6) biotypes were 14.7 and 14.6 micromoles CO(2) per square meter per second with I(50) values of 65.0 micromolar atrazine. The S biotype was larger and more productive than the R biotype at all harvests. At the harvest 57 days after planting, mean shoot dry weight was 33.2 and 8.7 grams for the S and R biotypes, respectively. The growth effect associated with chloroplast differences was shown in comparisons of the S biotype with the RxS(BC6) biotype and of the SxR(BC6) biotype with the R biotype. The RxS(BC6) biotype had 72% of the shoot dry weight of the S biotype while the R biotype had 55% of the shoot dry weight of the SxR(BC6) biotype. The RxS(BC6) and R biotypes produced about 73 and 62% of the leaf area of the S and SxR(BC6) biotypes, respectively. Relative growth rate was similar in biotypes with the same nuclear genome; however, instantaneous unit leaf rate was higher in the S compared to the RxS(BC6) biotype and in the SxR(BC6) compared to the R biotype. At 57 days after planting, the cumulative leaf area duration (i.e. photosynthetic opportunity) of the RxS(BC6) and R biotypes was 86 and 66% of that of the S and SxR(BC6) biotypes, respectively. Our data indicate that impaired chloroplast function in triazine resistant S. vulgaris biotypes limits growth and productivity at the whole plant level.

Journal Article↗

PubMed2000

Synthesis and characteristics of the human serum albumin-triazine chiral stationary phase.

Human serum albumin (HSA) was successfully bonded to silica with s-triazine as activator. The coupling reaction by this method was rapid and effective. The triazine-activated silica is relatively stable and can be installed for at least 1 month without obvious loss of reactivity when stored below 30 degrees C, pH below 7. It was observed that the amount of bound HSA reached 120 mg/g silica calculated from the UV absorbance difference of the HSA solution. d, l-tryptophan was selected as the probe solute to characterize the properties of HSA bonded s-triazine chiral stationary phase, and separation factor of 9.4 was obtained for d,l-tryptophan. Furthermore, the amount of effective HSA on silica was measured by high-performance frontal analysis, and only 16.8 mg/g silica was responsible for the resolution of d,l-tryptophan. These results indicate that the amount of both the bound and effective HSA on silica with triazine as activator was much higher than those by the Schiff base coupling method. Different kinds of enantiomers were resolved successfully on the aminopropylsilica-bonded HSA s-triazine chiral stationary phase.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed2005

Convenient synthesis of fused heterocyclic 1,3,5-triazines from some N-acyl imidates and heterocyclic amines as anticancer and antioxidant agents.

N-Acyl imidates (2), reacting with 5-amino pyrazole (3), 2-aminobenzimidazole (4), 3-amino-1,2,4-triazole (5), 3,5-diamino-1,2,4-triazole (6), and 5-aminotetrazole (7) give pyrazolo[1,5-a][1,3,5]triazine (8), benzo[4,5]imidazo[1,2-a][1,3,5]triazine (9), [1,2,4]triazolo [2,3-a][1,3,5]triazine (10), [1,2,4]tri azolo[2,3-a][1,3,5]triazin-5-ylamine (12), and tetrazolo-[1,5-a][1,3,5]triazine (14) derivatives, respectively. The synthesized compounds were characterized on the basis of IR, (1)H-NMR, (13)C-NMR, and mass spectral data and elemental analyses results. Five of the newly synthesized compounds, 8a, 9a, 10a, 12a, and 14a, were selected by National Cancer Institute and screened for their anticancer activity against three cancer cell lines MCF7, NCI-H460, and SF-268, where 12a exhibited moderate anti-proliferation potential. 12a was, thus, further tested for anticancer activity against 60 human cancer cell lines and showed moderate growth inhibition potency. 12a showed a high growth inhibitory activity against A498 renal cancer cell line. All of the newly synthesized compounds 8-10, 12 and 14 were tested for their antioxidant capacity where they exhibited very high activity, even higher than the widely used reference antioxidants butylated hydroxytoluene and 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox). Compound 12a also showed the highest antioxidant activity.

Amines↗

PubMed1978

Pharmacokinetics of Aryldihydro-s-triazines with antifolate activity II: Blood levels and their relevance to antineoplastic activity in rats.

Blood levels of three aryldihydro-s-triazines in rats were followed: 4,6-diamino-1,2-dihydro-2,2-dimethyl-1-phenyl-s-triazine (I), the prototype of the series; 4,6-diamino-1-(3,4-dichlorophenyl)-1,2-dihydro-2,2-dimethyl-s-triazine (II); and N-(m-tolyl)-p-(4,6-diamino-1,2-dihydro-2,2-dimethyl-s-triazin-1-yl)hydrocinnamide (III). The blood profiles obtained provide substantial evidence that III, but not II, was precipitated in the peritoneal cavity where it was injected. Precipitation after intraperitoneal injection may explain why III and similar triazines with long nonpolar chains have been reported to be more active against intraperitoneal Walker 256 tumor than is II, even though the latter compound is a far more potent inhibitor of Walker 256 dihydrofolate reductase and of tumor cell cultures in vitro. Precipitation in the peritoneal cavity also may be involved in the difficulty of obtaining the toxicity-free antineoplastic activity expected from certain aryldihydrotriazines selectively inhibiting neoplastic dihydrofolate reductase.

Animals↗

PubMed1987

Use of gas liquid chromatography/mass spectrometry for triazine herbicide residues analysis in forage and milk.

Residual s-triazines were isolated from forage and milk samples by methanol/chloroform extraction followed by column purification. The evaporated extracts were dissolved in acetone and analysed by gas chromatography with NPD detection and mass spectrometry. The detection limits for both methods were found to be about 5 approximately 10 ng of each s-triazine. The selective ions of the 10 s-triazines investigated (simazine, atrazine, propazine, terbuthylazine, cyanazine, desmetryne, ametryne, prometryne, terbutryne and methoprotryne) were chosen on the basis of an electron impact mass spectrometry study of the s-triazine standards and the whole mass spectra are given. Special attention was paid to the fragmentation of cyanazine and the general cleavage pathways of the s-triazines under investigation.

Animal Feed↗

PubMed2006

Effects of triazine herbicides on organophosphate insecticide toxicity in Hyalella azteca.

The frequent use of pesticides in agricultural and commercial settings has led some researchers to devote their attention to studying the effects of mixtures of these compounds as they co-occur in the environment. Recent studies have demonstrated the potentiating effects of triazine herbicides, such as atrazine and its analogs, to the toxicity of a variety of organophosphate (OP) insecticides. One such OP insecticide, chlorpyrifos, has been the topic of much concern because of its prevalence in the environment. This study focused on examining the effects of 10 select triazine herbicides at concentrations of 1 mumole/L (approximately 200 mug/L) to chlorpyrifos with Hyalella azteca. The compounds selected include atrazine, three of its degradation products, and six other herbicide active ingredients. Toxicity tests were performed using a two-way analysis of variance matrix design with effect levels determined by way of probit analysis. Atrazine was found to have the greatest acutely lethal effect to H. azteca, followed by its closest degradation product, deethylatrazine. Two of the six atrazine analogs, simazine and cyanazine, also showed significant effects to the insecticide's toxicity. Synergistic ratios (SRs) were calculated to compare the effect magnitudes for each of the herbicides. The highest ratio obtained was with atrazine (SR = 1.42). A majority of the past studies involving mixtures of triazines and OPs have examined the potentiation effects of active-use triazine herbicides on Chironomus species. However, compared with the acute effects previously obtained for Chironomus species, H. azteca show a higher tolerance to the presence of the triazine herbicides, even at levels often considered as being at the high end of environmentally relevant concentrations. When coupled with past studies from our laboratory, this research helps to provide a better understanding of the toxic effects of herbicide-insecticide interactions.

Amphipoda↗

PubMed2006

Treatability of chloro-s-triazines by conventional drinking water treatment technologies.

Recent research shows that herbicide atrazine (ATZ), simazine (SIM), and propazine (PROP), as well as their three chlorinated degrades-desethylatrazine (DEA), deisopropylatrazine (DIA), and didealkylatrazine (DDA)-may cause a common toxic effect in terms of endocrine disruption. The US Environmental Protection Agency (EPA) is currently considering a regulatory trigger based on the sum of these concentrations of these six chloro-s-triazines. While limited removal data exists for the parent compounds, little information is available for the degrades formed biologically and/or chemically in the environment and in the treatment plants. It is therefore critical to assess the removal efficiency in a typical water plant of the parent herbicides, as well as the daughter products. In this work, conventional drinking water treatment technologies were evaluated under typical water treatment plant conditions to determine their effectiveness in removing six chloro-s-triazines: ATZ, SIM, PROP, DEA, DIA, and DDA. Experiments were conducted using synthetic solutions prepared by spiking both distilled water and Missouri River water with the study compounds. Two powder activated carbons (PAC)--Calgon WPH and Norit HDB-were shown to be partially effective in removing the studied chloro-s-triazines. Ozonation efficiency varied, depending on different water sources, with respect to the removal of atrazine and didealkylatrazine. Coagulation/flocculation/sedimentation with alum and iron salts, excess lime/soda ash softening, and disinfection by free chlorine were all ineffective methods for removing chloro-s-triazines. It appears that chloro-s-triazine compounds are not readily removed by most conventional drinking water treatment processes, with the exception of use of activated carbon.

Herbicides↗

PubMed2001

Synthesis of pyrrolo[2,1-f][1,2,4]triazine C-nucleosides. Isosteres of sangivamycin, tubercidin, and toyocamycin.

Syntheses of pyrrolo[2,1-f][1,2,4]triazine C-nucleosides are reported. Treatment of pyranulose glycoside with aminoguanidine in acetic acid gave the corresponding semicarbazone in 96% yield. The ring transformation of the semicarbazone in dioxane afforded a 51% yield of 2-amino-7-(2,3,5-tri-O-benzoyl-beta-D-ribofuranosyl)pyrrolo[2,1-f]-[1,2,4]triazine. Vilsmeier formylation of the pyrrolotriazine gave the major product, 5-formylpyrrolo[2,1-f][1,2,4]triazine, in 69% yield. The aldehyde was treated with hydroxylamine hydrochloride in methanol to give aldoximes. Dehydration of aldoxime with trifluoromethanesulfonic anhydride and triethylamine in dichloromethane afforded 5-cyanopyrrolo[2,1-f][1,2,4]triazine in 44% yield. Conversion of the nitrile to the deprotected amide, 2-amino-7-(beta-D-ribofuranosyl)pyrrolo[2,1-f][1,2,4]triazine-5-carboxamide, was accomplished in 96% yield on treatment with 30% H2O2 in ethanol for 1 day at room temperature. Debenzoylation with sodium hydroxide solution produced deprotected C-nucleosides.

Antibiotics, Antineoplastic↗