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PubMed2006

2,3,7-Trisubstituted pyrazolo[1,5-d][1,2,4]triazines: functionally selective GABAA alpha3-subtype agonists.

Novel synthetic routes have been devised for the preparation of previously inaccessible 2,3,7-trisubstituted pyrazolo[1,5-d][1,2,4]triazines 2. These compounds are high affinity ligands for the GABA(A) benzodiazepine binding site and some analogues show functional selectivity for agonism at alpha3-containing receptors over alpha1-containing receptors with the lead compound being 32.

Binding Sites↗

PubMed2006

Discovery of [7-(2,6-dichlorophenyl)-5-methylbenzo [1,2,4]triazin-3-yl]-[4-(2-pyrrolidin-1-ylethoxy)phenyl]amine--a potent, orally active Src kinase inhibitor with anti-tumor activity in preclinical assays.

We describe the identification of [7-(2,6-dichlorophenyl)-5-methylbenzo [1,2,4]triazin-3-yl]-[4-(2-pyrrolidin-1-ylethoxy)phenyl]amine (3), a potent, orally active Src inhibitor with desirable PK properties, demonstrated activity in human tumor cell lines and in animal models of tumor growth.

Animals↗

PubMed2004

Effect of temperature on the disappearance of four triazine herbicides in environmental waters.

The influence of temperature on the disappearance of four s-triazine herbicides, terbuthylazine, simazine, atrazine and prometryn was studied in sea, river and groundwaters spiked with approx. 5 mg l(-1) of each during long-term laboratory incubation. Residues were analyzed by GC-NPD and confirmed by GC-MSD. No clean-up was necessary and a micro on-line method for the determination of herbicide residues was used. The results showed that temperature had little effect on the behaviour of the four herbicides in river and seawaters but strongly affected their behaviour in groundwater. Simazine was the most readily affected compound in sea, river and groundwaters, while terbuthylazine and atrazine were the most persistent in all cases, especially in riverwater. Half-lives ranged from 41 days (constant rate = 0.017 days(-1)) to 196 days (constant rate = 0.003 days(-1)) for simazine (40 degrees C) and terbuthylazine (20 degrees C), respectively, in riverwater. Only for terbuthylazine in riverwater was the remaining percentage at the end of the experiment higher than 50% (58%, 3.21 mg l(-1)). In the other cases, the remaining percentage varied from 4% (0.20 mg l(-1), 40 degrees C) to 43% (2.25 mg l(-1), 20 degrees C) for simazine and terbuthylazine, respectively, in groundwater.

Atrazine↗

PubMed2005

Toxicity of hexahydro-1,3,5-trinitro-1,3,5-triazine to larval zebrafish (Danio rerio).

Hexahydro-1,3,5-trinitro-1,3,5-triazine, a cyclonitramine commonly known as RDX, is used in the production of military munitions. Contamination of soil, sediment, and ground and surface waters with RDX has been reported in different places around the world. Acute and subacute toxicities of RDX have been relatively well documented in terrestrial vertebrates, but among aquatic vertebrates the information available is limited. The objective of this study was to characterize the acute toxicity of RDX to larval zebrafish. Mortality (LC50) and incidence of vertebral column deformities (EC50) were two of the end points measured in this study. The 96-h LC50 was estimated at 22.98 and 25.64 mgl(-1) in two different tests. The estimated no-observed-effective-concentration (NOEC) values of RDX on lethality were 13.27+/-0.05 and 15.32+/-0.30 mgl(-1); and the lowest-observed-effective-concentration (LOEC) values were 16.52+/-0.05 and 19.09+/-0.23 mgl(-1) in these two tests, respectively. The 96-h EC50 for vertebral deformities on survivors from one of the acute lethality tests was estimated at 20.84 mgl(-1), with NOEC and LOEC of 9.75+/-0.34 and 12.84+/-0.34 mgl(-1), respectively. Behavioral aberrations were also noted in this acute toxicity study, including the occurrence of whirling movement and lethargic behavior. The acute effects of RDX on survival, incidence of deformities, and behavior of larval zebrafish occurred at the high end of the most frequently reported concentrations of RDX in aquatic environments. The chronic effects of RDX in aquatic vertebrates need to be determined for an adequate assessment of the ecological risk of environmental RDX.

Animals↗

PubMed2005

Stir-bar sorptive extraction and thermal desorption-ion mobility spectrometry for the determination of trinitrotoluene and l,3,5-trinitro-l,3,5-triazine in water samples.

Stir-bar sorptive extraction (SBSE) is interfaced to ion mobility spectrometry (IMS) for the rapid detection of trace analytes, with the explosives, trinitrotoluene (TNT) and l,3,5-trinitro-l,3,5-triazine (RDX) shown as examples. SBSE retains its inherent advantages as a sensitive, straightforward, solventless, and inexpensive method. Additionally, the new SBSE-IMS technique exhibits excellent sensitivity, has onsite field analysis capabilities and provides the potential to detect and quantitate analytes that are difficult to accomplish using gas chromatography (GC) or high-performance liquid chromatography (HPLC). The SBSE-IMS technique is shown to be an effective method for the low-level detection of TNT and RDX from water with method standard deviation of 8.6% for TNT and 6.6% for RDX. The short desorption time of 60 s and analysis time of less than 20 ms along with limits of detection of 0.1 ng/mL for TNT and 1.5 ng/mL for RDX and render the method potentially useful for trace analysis. Desorption profiles showing the kinetics of analyte transfer from the stir-bar into the IMS are shown and discussed; the SBSE-IMS configuration shows very rapid desorption from the stir-bar, with the analytes completely transferred in most cases, in under 1 min.

Chemical Fractionation↗

PubMed2005

Rapid and ultrasensitive determination of ephedrine and pseudoephedrine derivatizated with 5-(4,6-dichloro-s-triazin-2-ylamino) fluorescein by micellar electrokinetic chromatography with laser-induced fluorescence detection.

This paper presents a micellar electrokinetic chromatography method with laser-induced fluorescence detection to analyze ephedrine (E) and pseudoephedrine (PE) after derivatizated with 5-(4,6-dichloro-s-triazin-2-ylamino) fluorescein. The optimum derivatization conditions were: 0.05 M Na2CO(3/NaHCO3 (pH 9.5), reaction time 30 min at 45 degrees C, molar ratio of DTAF to E and PE mixture 20:1. The baseline separation was achieved within 8 min with running buffer composed of 20 mM borate+20 mM SDS+15% acetonitrile (v/v) (adjusted pH 9.8), and applied voltage of 20 kV. Good linearity relationships (correlation coefficients: 0.9906 for E and 0.9941 for PE) between the peak heights and concentration of the analytes were obtained (2.5-50 ngmL(-1)). The detection limits for E and PE were 3.85 x 10(-4) and 1.41 x 10(-4)ngmL(-1), respectively, which indicated that the proposed method surpassed other chromatographic alternatives in terms of limit of detection by at least 10(3) folds. The method was applied to the analysis of the two alkaloids in ephedra herb plants and its preparations with recoveries in the range of 89.6-107.0%.

Chromatography, Micellar Electrokinetic Capillary↗

PubMed2006

Feasibility study of a reference material for water chemistry: long term stability of triazine and phenylurea residues stored in vials or on polymeric sorbents.

Matrix Reference Materials (MRM) are essential tools for the validation of analytical protocols. Nowadays, there are no such materials for the determination of herbicides in water. So, a feasibility study of a MRM for the analysis of triazines and phenylureas in water was carried out. Different kinds of candidates MRM were prepared: solutions of pesticides diluted in acetonitrile and stored in sealed vials or stored at the dry state after the evaporation of the solvent to dryness, pesticides stored on two different types of polymeric solid-phase extraction (SPE) sorbents after the percolation of drinking or river waters spiked with pesticides. The stability of these candidates MRM stored at various temperatures (room temperature, 0.5 degrees C or -18 degrees C) was studied over a period of approximately 1 year. Two different levels of concentration were studied for each kind of material. During the storage, some samples of each different MRM candidate were monthly analyzed by liquid chromatography. Results showed that, among the candidate materials, some of them presented satisfactory enough stability to consider a further certification. They were either pesticides in solution in sealed vials or pesticides stored on cartridges after the percolation of spiked water samples. However, it was shown that these different MRM candidates had to be stored at a temperature lower than 0.5 degrees C.

Chromatography, High Pressure Liquid↗

PubMed2006

On-fibre solid-phase microextraction coupled to conventional liquid chromatography versus in-tube solid-phase microextraction coupled to capillary liquid chromatography for the screening analysis of triazines in water samples.

This paper compares the advantages and disadvantages of two different configurations for the extraction of triazines from water samples: (1) on-fibre solid-phase microextraction (SPME) coupled to conventional liquid chromatography (LC); and (2) in-tube SPME coupled to capillary LC. In-tube SPME has been effected either with a packed column or with an open capillary column. A critical evaluation of the main parameters affecting the performance of each method has been carried out in order to select the most suitable approach according to the requirements of the analysis. In the on-fibre SPME configuration the fibre coating was polydimethylsiloxane (PDMS)-divinylbenzene (DVB). The limits of detection (LODs) obtained with this approach under the optimized extraction and desorption conditions were between 25 and 125 microg/L. The in-tube SPME approach with a C18 packed column (35 mm x 0.5 mm I.D., 5 microm particle size) connected to a switching micro-valve provided the best sensitivity; under such configuration the LODs were between 0.025 and 0.5 microg/L. The in-tube SPME approach with an open capillary column coated with PDMS (30 cm x 0.25 mm I.D., 0.25 microm of thickness coating) connected to the injection valve provided LODs between 0.1 and 0.5 microg/L. In all configurations UV detection at 230 nm was used. Atrazine, simazine, propazine, ametryn, prometryn and terbutryn were selected as model compounds.

Chromatography, Liquid↗

PubMed2005

Antinociceptive activity of new imidazolidine carbonyl derivatives. Part 4. Synthesis and pharmacological activity of 8-aryl-3,4-dioxo-2H,8H-6,7-dihydroimidazo[2,1-c] [1,2,4]triazines.

Synthesis and pharmacological activity of 8-aryl-3,4-dioxo-2H,8H-6,7-dihydroimidazo[2,1-c] [1,2,4]triazines (A) are presented. The title compounds were obtained from 1-aryl-2-hydrazinoimidazolines (1) by cyclization reaction with ethyl oxalate (2). They were tested for pharmacological activity in behavioral animal tests (A1, A3, A5, A6, A8, A9). With relatively low acute toxicity (LD50 in range from 1100 to over 2000 mg kg(-1), intraperitoneally, i.p.), some of them exhibited significant antinociceptive activity as the result of the 'writhing' test indicated. Especially strong antinociception for compound A8 and significant for A6 was observed in doses of 12.5-200 mg (0.00625-0.1 LD50) and 37.5-150 mg (0.025-0.1 LD50), respectively. Reversion of the antinociception for A1 and A8 produced in the 'writhing' test by 5 mg kg(-1) dose of naloxon can suggest an opioid-like mechanism of their analgesic activity. Additionally, compound A9 reduced number of the "head twitch" episodes after 5-hydroxytryptophan (5-HTP) administration with no antinociceptive effect at all and compound A3 showed significant protection in the pentylentetrazol-induced seizure model. Differences observed in the activity spectrum between A8 and A9 derivatives can be explained on the base of difference in the amido-imido tautomeric equilibrium observed between these two compounds.

Amides↗

PubMed2006

Synthesis, structure and anticancer activity of novel alkenyl-1,3,5-triazine derivatives.

A series of novel 4-(E)-ethenyl-6-alkylamino-1,3,5-triazin-2-ylamine derivatives 9-17 have been synthesized by a Wittig reaction of corresponding alkyltriphenylphosphonium bromides 5-8 with (hetero)aromatic aldehydes. The E configuration of these alkenes was confirmed by 1H NMR spectroscopic data. All the compounds prepared were screened at the National Cancer Institute (NCI) for their activity against a panel of 56 tumor cell lines and relationship between structure and in vitro antitumor activity is discussed. The most active compounds 14 and 17 showed 50% growth inhibitory activity in low micromolar concentrations against renal cancer A498 cell line and colon cancer cell line COLO 205, respectively.

Alkenes↗

PubMed2006

Synthesis, crystal structure and anticancer activity of novel derivatives of ethyl 1-(4-oxo-8-aryl-4,6,7,8-tetrahydroimidazo[2,1-c][1,2,4]triazin-3-yl)formate.

Synthesis and anticancer activity of ethyl 1-(4-oxo-8-aryl-4,6,7,8-tetrahydroimidazo[2,1-c][1,2,4]triazin-3-yl)formates (7-12) are presented. The title compounds were obtained by two independent synthesis methods from 1-aryl-2-hydrazono-imidazolidines (1-aryl-2-hydrazino-imidazolines) (1-6) by cyclocondensation reaction with diethyl 2-(hydroxyimino)malonate (A) and diethyl 2-oxomalonate (B). Molecular structure of synthesized compounds was confirmed by IR, (1)H NMR, EI-MS spectra, elemental analysis and X-ray crystallography for 12. Compounds 10 and 11 exhibited anticancer activity towards following cancer cells: LS180 (ECACC 87021202, human Caucasian colon adenocarcinoma cells), SiHa (ECACC 85060701, uterus cancer cells), T47D (ECACC 85102201, human breast carcinoma cells). Compound 10 was found to be the most active against SiHa cancer line; its GI was 41 and 52%, respectively in both examined concentrations (10 and 50 microg ml(-1)), whereas compound 11 had the highest potential to reduce the growth of LS180 and SiHa cancer lines, especially in a higher dose (50 microg ml(-1)). Moreover, the distinctly marked lower cytotoxicity of tested compounds against normal cell lines (HSF, human skin fibroblast cells and Vero African Green Monkey Kidney cells, GMK clone) and almost two-times higher against cancer cell lines was confirmed. Also antibacterial activity of starting 1-(2-chlorophenyl)-2-hydrazonoimidazolidine hydroiodide (4) is presented. Molecular structure of 4 was confirmed by IR, (1)H NMR, (13)C NMR, EI-MS spectra, elemental analysis and (1)H-(1)H COSY, HMBC and HMQC correlations. The marked antibacterial activity for this compound in relation to Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 with equal minimal inhibitory concentration values of 15.62 and 15.62 microg ml(-1) was found.

Animals↗

PubMed2006

Synthesis and antibacterial activity of various substituted s-triazines.

Series of substituted-s-triazines (1-22) were synthesized and evaluated for their in vitro antibacterial activity against six representative Gram-positive and Gram-negative bacterial strains. Many compounds have displayed comparable antibacterial activity against Bacillus sphaericus and significantly active against other tested organisms with reference to streptomycin.

Anti-Bacterial Agents↗

PubMed2007

Synthesis and characterization of cobalt(II), nickel(II), copper(II) and zinc(II) complexes with Schiff base derived from 4-amino-3-mercapto-6-methyl-5-oxo-1,2,4-triazine.

A few (1:1) and (1:2) metal complexes of cobalt(II), nickel(II), copper(II) and zinc(II) have been isolated with ligand derived from the condensation of 4-amino-3-mercapto-6-methyl-5-oxo-1,2,4-triazine with 2-acetylpyridine (L(1)) and characterized by elemental analysis, conductivity measurements, infrared, electronic, (1)H NMR spectral data, magnetic and thermogravimetric analyses. Due to insolubility in water and most of the common organic solvents and infusibility at higher temperatures, all the complexes are thought to be polymeric in nature. A square-planar geometry was suggested for copper(II) and octahedral proposed for cobalt(II), nickel(II) and zinc(II). Some of the chemically synthesized compounds have been screened in vitro against the three Gram-positive (Staphylococcus aureus, Staphylococcus epidermidis and Bacillus subtilis) and two Gram-negative (Salmonella typhi and Escherichia coli) organisms. It is observed that the coordination of metal ion has pronounced effect on the microbial activities of the ligand. The metal complexes have higher antimicrobial effect than the free ligands.

Anti-Bacterial Agents↗

PubMed2006

Procedures of trophic chain samples preparation for determination of triazines by HPLC and metals by ICP-AES methods.

The aim of this research was monitoring the distribution of atrazine and simazine as well as metals Pb, Cd, Zn, Al, Co, Ni, and V along with trophic chains: soil-vegetables and soil, carrot or grass and meat. Different techniques of herbicides extraction by means of many solvents were examined. Triazines were analysed by means of HPLC, metals by means of ICP-AES. Detection limits: LOD=0.2 microg ml(-1), determination limits: LOQ=0.73 microg ml(-1) for atrazine and LOD=0.3 microg ml(-1), LOQ=1.12 microg ml(-1) for simazine were obtained. The content (microg g(-1)) of simazine in soil was in range: 3.45-8.60, in vegetable roots: 6.62-38.15, in vegetable leaves: 2.45-31.71, in rabbit fat: 0.13-49.90. The content (microg g(-1)) of atrazine in soils was in range: 11.9-13.03, in vegetable roots: 13.61-92.90. In analysed material the particular metals after microwave or dry digestion were determined in range (microg g(-1)): Pb: 6.48-43.18; Cd: 0.11-0.57; Zn: 8.79-51.90; Al: 10.22-24.48; Co: 0.18-3.89; Ni: 0.37-6.36; V: 0.29-1.48.

Aluminum↗

PubMed2004

Interaction of L-glutamate oxidase with triazine dyes: selection of ligands for affinity chromatography.

Glutamate oxidase (GOX, EC 1.4.3.11) from Streptomyces catalyses the oxidation of L-glutamate to alpha-ketoglutarate. Its kinetic constants for L-glutamate were measured equal to 2 mM for Km and 85.8 s(-1) for kcat. BLAST search and amino acid sequence alignments revealed low homology to other L-amino acid oxidases (18-38%). Threading methodology, homology modeling and CASTp analysis resulted in certain conclusions concerning the structure of catalytic alpha-subunit and led to the prediction of a binding pocket that provides favorable conditions of accommodating negatively charged aromatic ligands, such as sulphonated triazine dyes. Eleven commercial textile dyes and four biomimetic dyes or minodyes, bearing a ketocarboxylated-structure as their terminal biomimetic moiety, immobilized on cross-linked agarose gel. The resulted mini-library of affinity adsorbents was screened for binding and eluting L-glutamate oxidase activity. All but Cibacron Blue 3GA (CB3GA) affinity adsorbents were able to bind GOX at pH 5.6. One immobilized minodye-ligand, bearing as its terminal biomimetic moiety p-aminobenzyloxanylic acid (BM1), displayed the higher affinity for GOX. Kinetic inhibition studies showed that BM1 inhibits GOX in a non-competitive manner with a Ki of 10.5 microM, indicating that the dye-enzyme interaction does not involve the substrate-binding site. Adsorption equilibrium data, obtained from a batch system with BM1 adsorbent, corresponded well to the Freundlich isotherm with a rate constant k of 2.7 mg(1/2)ml(1/2)/g and Freundlich isotherm exponent n of 1. The interaction of GOX with the BM1 adsorbent was further studied with regards to adsorption and elution conditions. The results obtained were exploited in the development of a facile purification protocol for GOX, which led to 335-fold purification in a single step with high enzyme recovery (95%). The present purification procedure is the most efficient reported so far for L-glutamate oxidase.

Adsorption↗

PubMed2006

Identification of a metabolite of atrazine, N-ethyl-6-methoxy-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, upon incubation with rat liver microsomes.

Atrazine is an herbicide which has shown potential antimalarial effects both in vitro and in vivo in rats. In order to study the metabolism of atrazine in rat livers, we developed a sensitive LC/MS/MS method for the identification of atrazine and several of its metabolites. Using this method, we identified one previously unreported metabolite with a mass of 211 Da in addition to two known metabolites. This new metabolite was confirmed to be N-ethyl-6-methoxy-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, also known as atraton, by comparison of the LC/MS/MS mass spectra and the retention time to those of a commercial standard.

Animals↗

PubMed2005

Separation, preconcentration and determination of silver ion from water samples using silica gel modified with 2,4,6-trimorpholino-1,3,5-triazin.

A new modified silica gel using 2,4,6-trimorpholino-1,3,5-triazin was used for separation, preconcentration and determination of silver ion in natural water by atomic absorption spectrometry (AAS). This new bonded silica gel was used as an effective sorbent for the solid-phase extraction (SPE) of silver ion from aqueous solutions. Experimental conditions for effective adsorption of trace levels of silver ion were optimized with respect to different experimental parameters in column process. Common coexisting ions did not interfere with the separation and determination of silver at pH 3.5 so that silver ion completely adsorbed on the column. The preconcentration factor is 130 (1 mL elution volume for a 130 mL sample volume). The relative standard deviation (R.S.D.) under optimum conditions is 3.03% (n=5). The accuracy of the method was estimated by using spring and tap water samples that were spiked with different amounts of silver ion. The adsorption isotherm of silver ion was obtained. The capacity of the sorbent at optimum conditions has been found to be 384 microg of silver per gram of sorbent.

Adsorption↗

PubMed2005

Photocatalytic degradation of triazinic ring-containing azo dye (Reactive Red 198) by using immobilized TiO2 photoreactor: bench scale study.

The decolorization and degradation of triazinic ring-containing azo dye by using TiO(2)-immobilized photoreactor is reported. A simple and easy method was used for the immobilization of photocatalyst. Reactive Red 198 (RR 198) was used as model compound. Photocatalytic degradation processes were performed using a 5 L (bench scale) solution containing dye. Batch mode immersion type method was used for the treatment of dye solution. UV-vis, ion chromatography (IC) and chemical oxygen demand (COD) analyses were employed to evaluate the results of the photocatalytic degradation of RR 198. Dye solution was completely decolorized in relatively short time (35 min) after UV irradiation in combination with hydrogen peroxide. The results verified that all of the dye molecules were destructed. Kinetics analysis indicates that the dye photocatalytic decolorization rates followed first order model (R(2) = 0.99). Ion chromatography analysis was used to investigate the formation and destruction of aliphatic carboxylic acids and formation of inorganic anions during the process. Formate and oxalate anions were detected as main aliphatic carboxylic intermediates, which were further oxidized slowly to CO(2). UV/TiO(2)/H(2)O(2) process proved to be capable of successful decolorization and degradation of the RR 198.

Azo Compounds↗