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PubMed2005

The design and synthesis of a herbicide targeted library of N-[1-(1,3-benzoxazol-2-yl)alkyl]-6-alkyl-1,3,5-triazine-2,4-diamines.

Amino acids were immobilised by attaching them via a carbamate linker to Wang resin. These intermediates were converted to 1-(1,3-benzoxazol-2-yl)alkanamines over three steps, followed by coupling with 4-alkyl-6-chloro-1,3,5-triazine-2-amines to furnish the desired N-[1-(1,3-benzoxazol-2-yl)alkyl]-6-alkyl-1,3,5-triazine-2,4-diamines. Physico-chemical property profiles were used to support design and development of a combinatorial library. The synthetic methodology described herein was validated with the production of a herbicide targeted library of 300 members.

Agrochemicals↗
PubMed2001

A combined application of reaction prediction and infrared spectra simulation for the identification of degradation products of s-triazine herbicides.

Substance identification in analytical chemistry is usually performed by comparing an experimental spectrum with a reference spectrum. Especially in environmental chemistry, reference spectra from databases are only available for a limited number of compounds. The combination of the reaction prediction system EROS and of infrared spectra simulation is a powerful tool for computer-assisted substance identification. First, possible degradation products of a chemical are predicted and then the infrared spectra of all these compounds are simulated. Comparison of the simulated infrared spectra with experimental spectra allows one to identify the structure of compounds. The method is demonstrated with the example of s-triazine herbicides.

Computer Simulation↗
PubMed2001

Separation of 4-dimethylamino-6-(4-methoxy-1-naphthyl)-1,3,5-triazine-2-hydrazine derivatives of carbonyl compounds by reversed-phase capillary electrochromatography.

4-Dimethylamino-6-(4-methoxy-1-naphthyl)-1,3,5-triazine-2-hydrazine (DMNTH) is a novel derivatizing reagent specially designed for the determination of carbonyl compounds. In this work, we describe the separation of DMNTH-derivatized carbonyl compounds by reversed-phase capillary electrochromatography (CEC). After systematic investigations of the effects of experimental conditions viz. pH and concentration of buffer, type of stationary phase, injection volume of sample, organic modifier, and temperature, optimal conditions were found. The sample compounds, which were separated with gradient high performance liquid chromatography (HPLC), were separated by CEC under isocratic elution due to the high efficiency. Comparisons of separations by CEC and micellar electrokinetic chromatography (MEKC) were made.

Carbonic Acid↗
PubMed2002

A biosensor for the detection of triazine and phenylurea herbicides designed using Photosystem II coupled to a screen-printed electrode.

A biosensor for the detection of triazine- and phenylurea-type herbicides was constructed using isolated Photosystem II (PS II) complexes as a biosensing element. PSII isolated from the thermophilic cyanobacterium Synechococcus elongatus was immobilized on the surface of a screen-printed sensor composed of a graphite working electrode and Ag/AgCl reference electrode deposited on a polymeric substrate. The biosensor was mounted in a flow microcell with illumination. The principle of the detection was based on the fact that herbicides selectively block PSII electron transport activity in a concentration-dependent manner. Changes of the activity were registered amperometrically as the rate of photoreduction of an artificial electron acceptor. The setup resulted in a reusable herbicide biosensor with a good stability (half-life of 24 h) and limit of detection of approximately 10(-9) M for diuron, atrazine and simazine.

Biosensing Techniques↗
PubMed2005

Synthesis and evaluation of a new biselector s-triazine based chiral stationary phase for enantioselective HPLC: potentiality of the approach and perspectives.

A s-triazine scaffold bearing a free and a protected amino group was used for connecting two different chiral auxiliaries, whose enantiodiscriminating capabilities in enantioselective chromatography are well documented. A biselector system was synthesized and, after linkage to silica gel, used for the chromatographic resolution of different racemic analytes, chosen among the compounds resolved by the two different isolated chiral auxiliaries. The obtained chromatographic results were compared with literature data related to the use of the two chiral stationary phases (CSPs) whose chiral moieties constitute the biselector CSP, allowing us to gain useful information about potentialities and limitations of this approach for obtaining independent CSPs having broader applicability with respect to the classical independent monoselector CSPs.

Chromatography, High Pressure Liquid↗
PubMed1978

Metabolism of [14C] terbutryn (2-(t-butylamino)-4-(ethylamino)-6-(methylthio-s-triazine) by rats and goat.

Sixteen metabolites of terbutryn were isolated from the urine and feces of either rats or a goat given single oral doses of terbutryn-[14C](2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine). The metabolites resulted from one or more of the following changes: S-demethylation, conversion of the methylthio group to a hydroxy group; N-deethylation; oxidation of the terminal carbon of the ethyl group to a carboxylic acid; oxidation of a terminal carbon of the t-butyl group to either an alcohol or a carboxylic acid; or conjugation with glucuronic acid.

Animals↗
PubMed1978

Mass spectral characterization of the glucuronide conjugates of terbutryn (2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine) metabolites from rats and goat.

Five metabolities from terbutyrn (2-(t-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine) were characterized to be glucuronide conjugates by interpretation of mass spectral data of their trimethylsilyl derivatives. These were isolated from rat and goat urine. Three of these glucuronides were characterized to be triazinyl-S-glucuronides and two were characterized to be alkyl-O-glucuronides.

Animals↗
PubMed2006

6-alkylthio-4-[1-(2,6-difluorophenyl)alkyl]-1H-[1,3,5]triazin-2-ones (ADATs): novel regulators of cell differentiation and proliferation.

Novel triazine analogues of 5-alkyl-2-alkylthio-6-[1-(2,6-difluorophenyl)alkyl]-3,4-dihydropyrimidin-4(3H)-ones (F(2)-DABOs), previously described by us as nonnucleoside HIV-1 reverse transcriptase inhibitors (NNRTIs), were tested for their antiproliferative and cytodifferentiating activity on the A-375 human melanoma cell line. Most of the tested derivatives were effective in decreasing cell proliferation, facilitating morphological differentiation, and reprogramming gene expression. All these effects were reversible upon withdrawal of RT inhibitors. Among the compounds tested, 3 f showed the highest antiproliferative effect, whereas compound 6 c, although not affecting cell proliferation, is endowed with a strong cytodifferentiating effect, which is probably related to a marked upregulation of the e-cad gene. These results support the potential of NNRTIs as valuable antitumor agents.

Cell Differentiation↗
PubMed2004

Optimization of the separation of a group of triazine herbicides by micellar capillary electrophoresis using experimental design and artificial neural networks.

The micellar electrokinetic chromatography separation of a group of triazine compounds was optimized using a combination of experimental design (ED) and artificial neural network (ANN). Different variables affecting separation were selected and used as input in the ANN. A chromatographic exponential function (CEF) combining resolution and separation time was used as output to obtain optimal separation conditions. An optimized buffer (19.3 mM sodium borate, 15.4 mM disodium hydrogen phosphate, 28.4 mM SDS, pH 9.45, and 7.5% 1-propanol) provides the best separation with regard to resolution and separation time. Besides, an analysis of variance (ANOVA) approach of the MEKC separation, using the same variables, was developed, and the best capability of the combination of ED-ANN for the optimization of the analytical methodology was demonstrated by comparing the results obtained from both approaches. In order to validate the proposed method, the different analytical parameters as repeatability and day-to-day precision were calculated. Finally, the optimized method was applied to the determination of these compounds in spiked and nonspiked ground water samples.

Chromatography, Micellar Electrokinetic Capillary↗
PubMed2006

Analysis of triazines by capillary electrochromatography/electrospray ionization-mass spectrometry using a low-flow sheath liquid interface.

CEC-MS has been used for the analysis of eight-triazine herbicides. It showed significantly better S/N ratio than reversed EOF CE-MS and MEKC-MS, due to the lack of a surfactant in the separation buffer. By optimizing the pH, the organic content of the running buffer, and the separation potential, optimal separation was achieved within 18 min using a running buffer of pH 7.0, containing 70% v/v ACN, and an applied voltage of 17 kV. Gradient CEC showed superior separation when compared with isocratic elution. The combination of a tapered CEC column and a low-flow interface confers several advantages including better sensitivity, low dead volume, and independent control of the conditions used for CEC separation and ESI analysis.

Capillary Electrochromatography↗
PubMed1995

Stimulation of bovine sperm motility and respiration by the triazine dye cibacron blue F3GA.

Bovine sperm motility and respiration were stimulated by the triazine dye Cibacron Blue F3GA (CB), which may operate as a nucleotide mimic. CB stimulation of respiration was half-maximal at about 35 microM and respiration reached maximal levels about 1.5 minutes after CB addition. Respiratory stimulation was preceded by a transient increase in cytosolic cAMP. Sperm cAMP titers were elevated from 5 to 10 pmoles/10(8) cells within 30 seconds of CB addition, but rapidly dropped to a stable level of about 7.5 pmoles/10(8) cells. CB was a potent inhibitor of sperm membrane adenylyl cyclase and inhibited respiration in permeabilized cells. Taken together, the data indicated that CB stimulation was not manifested via the cytosol. In addition, a nonpermeant blue dextran preparation synthesized with CB also stimulated sperm respiration and motility. CB inhibited sperm membrane phosphodiesterase activity, suggesting that the transient pulse of cAMP resulted from CB interaction with this enzyme in the sperm membrane.

Adenylyl Cyclase Inhibitors↗
PubMed2006

Rapid bidirectional allele-specific PCR identification for triazine resistance in higher plants.

Triazine resistance is reported to be due to chloroplast herbicide target insensitivity in most species, and this is most often caused by a Ser(264)-Gly mutation at the D1 protein. In order to ascertain whether this mutation is really predominant amongst resistant plants, and also for gene flow studies, a rapid test is needed that allows the testing of large quantities of plants. Here a bidirectional allele-specific PCR (polymerase chain reaction) identification is proposed. The designed primers were shown to be universal in the three grass and three broadleaf species examined.

Alleles↗
PubMed2003

Thermal and metabolic factors affecting bioaccumulation of triazine herbicides by rainbow trout (Oncorhynchus mykiss).

The bioaccumulation of the triazine herbicides terbutryn and terbuthylazine in rainbow trout was investigated at water temperatures of 4 degrees C, 10 degrees C, and 17 degrees C. The synergetic effect of water temperature and herbicide on fish liver detoxification metabolism was also studied by measuring liver ethoxyresorufin-O-deethylase (EROD) and UDP-glucuronosyltransferase (UDPGT) activities. The bioaccumulation of terbutryn increased significantly with increasing water temperature. However, temperature seemed to have no effect on the bioaccumulation of terbuthylazine. Both chemicals decreased the measured enzyme activities. Also, temperature effects were significant. In all tests the highest liver EROD activities were measured in fish exposed to a water temperature of 4 degrees C, and the activities decreased with increasing water temperature. The thermal effects on fish liver UDPGT activity differed between the herbicides. The highest activities at a water temperature of 4 degrees C were measured in fish exposed to terbutryn, whereas fish exposed to terbuthylazine had the highest liver UDPGT activities at 17 degrees C. Measuring liver detoxification metabolism together with bioaccumulation increases the understanding of bioaccumulation of chemicals in different environmental conditions.

Animals↗
PubMed1994

Purification of human cholesteryl ester transfer protein by affinity chromatography on immobilized triazine dyes.

Human cholesteryl ester transfer protein was purified from lipoprotein-depleted serum or plasma in a three-step procedure utilizing commercially available triazine dyes immobilized on agarose. The method used consisted of successive chromatography steps on Reactive Red 120 agarose (Procion Red H-E3B, Cibachron Brilliant Red 4G-E), CM Sepharose, and Reactive Yellow 86 agarose (Procion Yellow M-8G). Upon analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the resultant protein preparation displayed two bands of variable intensity. The two components had apparent molecular weights of approximately 64,000 and approximately 65,000, respectively. Both bands reacted strongly to a monoclonal antibody directed against an epitope consisting of the last eight amino acids at the carboxy terminus of human CETP. Yields of cholesteryl ester transfer activity are 10-40% of the activity present in lipoprotein-depleted serum. The activity is approximately 50,000- to 100,000-fold purified relative to the starting material.

Amino Acid Sequence↗
PubMed1986

Preclinical toxicology, pharmacokinetics and formulation of N2,N4,N6-trihydroxymethyl-N2,N4,N6-trimethylmelamine (trimelamol), a water-soluble cytotoxic s-triazine which does not require metabolic activation.

N2,N4,N6-Trihydroxymethyl-N2,N4,N6-trimethylmelamine (Trimelamol) is a water-soluble synthetic s-triazine which, unlike hexamethylmelamine (HMM) and pentamethylmelamine (PMM), does not require metabolic activation. The physico-chemical characteristics of Trimelamol were studied with the aim of overcoming the problems of chemical instability, low solubility and polymerisation which had hindered the development of the drug for clinical use. Trimelamol had similar activity to PMM against the murine PC6 plasmacytoma, but enhanced activity with respect to PMM against the Walker 256 carcinosarcoma in the rat, a species which metabolizes PMM less efficiently. Pharmacokinetic studies in mouse, rat and man did not show the major species differences characteristic of PMM. The drug exhibited similar toxicity to PMM against rodents, but had virtually no neurotoxicity. The potential advantages of Trimelamol over previously tested melamines are discussed.

Altretamine↗
PubMed1979

The use of sym-triazine trichloride in RNA-protein cross-linking studies with Escherichia coli ribosomal subunits.

The reagent sym-triazine trichloride is used as a bifunctional reagent to generate RNA-protein cross-links within intact ribosomal subunits from E. coli. The reaction takes place in a stepwise manner, involving substitution of one chlorine atom at 12 degrees and pH 8, and substitution of the second at 40 degrees and pH 6. The cross-linked proteins are analysed by two-dimensional electrophoresis, and the existence of a stable cross-linkage is demonstrated by isolating protein-oligonucleotide complexes from 32P-labelled subunits. The proteins cross-linked are S3 and S4 in the 30S subunit, and L2 in the large subunit, together with smaller amounts of other proteins. The reagent should prove useful in topographical studies of the E. coli ribosome as it is a rigid molecule and generates very short cross-links.

Electrophoresis↗
PubMed1988

Analysis of triazine herbicides residues in butter and pasteurized milk.

A method has been developed for the determination of atrazine, cyanazine, prometryn, simazine, and terbutryn residues in butter. The residues were extracted from the matrix with a mixture of petroleum ether/methanol (3 + 1), and from the separated water-methanol phase extraction was carried out with chloroform. The extract was cleaned up on an alumina column. Capillary glass liquid chromatography using a 15 m x 0.32 mm glass capillary column coated with OV-1 and an alcali flame ionization detector were employed for the analysis of the residues. The analyses were evaluated by the internal standard method, using metribuzin as the internal standard. The recovery of the method was 68.7%-79.8% for the individual herbicides under study at the fortification level of 0.1 mg.kg-1 and 79.2%-91.9% at the fortification level of 0.02 mg.kg-1. The determination limit of the method was 0.005 mg.kg-1. When centrifuging full milk, residues of triazines were partitioned between the water and fat phases, whereby 17%-82% of the residues were transferred to the milk fat. Samples of commercial butter were analysed and found to contain 0.005-0.023 mg.kg-1 atrazine.

Animals↗