Search results for "triazines"
showing 10 items of 61 documents
Azapropazone binding to human serum albumin
1980
Azapropazone, a new non-steroidal antiinflammatory drug, is strongly bound to human serum albumin. As revealed by Scatchard analysis, one high-affinity binding site with an association constant of about 1.2 x 10(6)M-1 and two low-affinity binding sites with association constants of about 0.05 x 10(6)M-1 were found. While the high-affinity binding site of azapropazone is clearly not identical with the diazepam or digitoxin binding sites of human serum albumin, contradictory evidence was found by optical measurements and displacement studies for the similarity of the azapropazone and the warfarin binding site of human serum albumin. At present, it is suggested that both drugs bind to differen…
Combination of supported liquid membrane and solid-phase extraction for sample pretreatment of triazine herbicides in juice prior to capillary electr…
2002
A possibility of a combination of supported liquid membrane (SLM) and solid-phase extraction (SPE) for the determination of atrazine at microgram level in different type of fruit juices is presented. In comparison to SPE extraction from juice samples, the application of SLM-SPE enrichment provides much cleaner extracts and the possibility of lowering the limit of detection as low as 30 microg/l. However, it was also shown that by appropriate manipulation of SLM extraction conditions mainly flow-rate of donor phase and volume ratio between donor and acceptor phase, the level of detection can be further decreased to 10 microg/l. The results suggest that the application of SLM extraction prior…
A sustainable on-line CapLC method for quantifying antifouling agents like irgarol-1051 and diuron in water samples: Estimation of the carbon footpri…
2016
In this work, in-tube solid phase microextraction (in-tube SPME) coupled to capillary LC (CapLC) with diode array detection has been reported, for on-line extraction and enrichment of booster biocides (irgarol-1051 and diuron) included in Water Frame Directive 2013/39/UE (WFD). The analytical performance has been successfully demonstrated. Furthermore, in the present work, the environmental friendliness of the procedure has been quantified by means of the implementation of the carbon footprint calculation of the analytical procedure and the comparison with other methodologies previously reported. Under the optimum conditions, the method presents good linearity over the range assayed, 0.05-1…
The dual PI3K/mTOR inhibitor PKI-587 enhances sensitivity to cetuximab in EGFR-resistant human head and neck cancer models
2014
Background:Cetuximab is the only targeted agent approved for the treatment of head and neck squamous cell carcinomas (HNSCC), but low response rates and disease progression are frequently reported. As the phosphoinositide 3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) pathways have an important role in the pathogenesis of HNSCC, we investigated their involvement in cetuximab resistance.Methods:Different human squamous cancer cell lines sensitive or resistant to cetuximab were tested for the dual PI3K/mTOR inhibitor PF-05212384 (PKI-587), alone and in combination, both in vitro and in vivo.Results:Treatment with PKI-587 enhances sensitivity to cetuximab in vitro, even in the co…
Recent advances in the development of cyclin-dependent kinase 7 inhibitors.
2019
Abstract Cyclin dependent kinase 7 (CDK7) plays a double role as it activates several other cyclin dependent kinases and participates to the initiation of transcription. This kinase is overexpressed in various types of tumors. Relatively few selective CDK7 inhibitors have been up to now disclosed. Most of these inhibitors belong to two chemical families: pyrazolopyrimidines and pyrazolotriazines on one side and pyrimidines on another side. They also differ by their molecular mechanism of action. Some are acting as competitive inhibitors and some others are covalent inhibitors. With these tools, the understanding of the potential therapeutic interest of CDK7 inhibitors in cancer is rapidly g…
Hierarchical Self-Organization of Perylene Bisimide–Melamine Assemblies to Fluorescent Mesoscopic Superstructures
2000
A series of three perylene tetracarboxylic acid bisimide dyes 3a-c bearing phenoxy substituents at the four bay positions of the perylene core were synthesized and their complexation behavior to complementary ditopic dialkyl melamines 8a-c was investigated. Binding constants and Gibbs binding energies for the hydrogen bonds between the imide and the complementary melamine moiety have been determined in several solvents by NMR and UV/Vis titration experiments with monotopic model compounds 5 and 9. The effects of the solvent polarity and specific solvent-solute interactions on the degree of polymerization of (3 x 8)n are discussed, and a general formula to estimate the chain length of [AA-BB…
Determination of triazines and organophosphorus pesticides in water samples using solid-phase extraction.
1991
Abstract Octadecyl (C 18 )-bonded porous silica was evaluated for the extraction of triazine and organophosphorus pesticides from natural water. The extraction results showed an effective performance when 1 l of water was passed through small glass columns containing 500 mg of 50–100-μm C 18 bonded porous silica. The absorbed compounds were removed with ethyl acetate, evaporated to 200 μl and determined by gas chromatography. The overall average recoveries were greater than 85% except for dimethoate and trichlorfon. Application of this procedure to the analysis of natural water samples gave results that agree well with those obtained by solvent extraction methods.
Effect of solvents on the selectivity of terbutylazine imprinted polymer sorbents used in solid-phase extraction
2002
A solid-phase extraction sample preparation method using a molecularly imprinted polymer (MIP) selective for the triazine type pesticide terbutylazine has been developed. The method involves preconcentration from large volumes of water samples on a C18 disk coupled to selective clean-up on the MIP. The method has been optimised by studying the recovery and retention of terbutylazine and some other structurally related triazine derivates as a function of the selective washing solvent used. The effect of the water content of the selective washing solvent was also investigated on the recovery of the MIP. River water samples were analysed with the coupled technique, and efficient clean-up of th…
New benzothieno[3,2-d]-1,2,3-triazines with antiproliferative activity: synthesis, spectroscopic studies, and biological activity.
2014
New benzothieno[3,2-d]-1,2,3-triazines, together with precursors triazenylbenzo[b]thiophenes, were designed, synthesized and screened as anticancer agents. The structural features of these compounds prompted us to investigate their DNA binding capability through UV–vis absorption titrations, circular dichroism, and viscometry, pointing out the occurrence of groove-binding. The derivative 3-(4-methoxy-phenyl)benzothieno[3,2-d]-1,2,3-triazin-4(3H)-one showed the highest antiproliferative effect against HeLa cells and was also tested in cell cycle perturbation experiments. The obtained results assessed for the first time the anticancer activity of benzothieno[3,2-d]-1,2,3-triazine nucleus, and…
Genetic potential, diversity and activity of an atrazine-degrading community enriched from a herbicide factory effluent
2008
Aims: To characterize an atrazine-degrading bacterial community enriched from the wastewater of a herbicide factory. Methods and Results: The community mineralized 81·4 ± 1·9% of [14C-ring]atrazine and 31·0 ± 1·8% of [14C-ethyl]atrazine within 6 days of batch cultivation in mineral salts medium containing atrazine as the sole nitrogen source. Degradation activity of the community towards different chloro- and methylthio-substituted s-triazine compounds was also demonstrated. Restriction analysis of amplified 16S rDNA revealed high diversity of bacterial populations forming the community, with Pseudomonas species dominating in the clone library. Atrazine-degrading genetic potential of the …