Relevant bibliographies by topics / Pure compounds

Academic literature on the topic 'Pure compounds'

Author: Grafiati
Published: 8 June 2024

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Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Journal articles on the topic "Pure compounds":

1

Babalola, F. U., and A. A. Susu. "Stability Limit Determination for Pure Compounds." Petroleum Science and Technology 26, no. 12 (July 21, 2008): 1481–97. http://dx.doi.org/10.1080/15567030701776783.

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2

Linde, Bogumił B. J., and Nikołaj B. Lezhnev. "Ultrasonic spectroscopy of pure cyclic compounds." Ultrasonics 44 (December 2006): e1467-e1470. http://dx.doi.org/10.1016/j.ultras.2006.05.146.

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López Cortés, José Guadalupe, Sandrine Vincendeau, Jean-Claude Daran, Eric Manoury, and Maryse Gouygou. "Three new enantiomerically pure ferrocenylphosphole compounds." Acta Crystallographica Section C Crystal Structure Communications 62, no. 5 (April 13, 2006): m188—m191. http://dx.doi.org/10.1107/s0108270106010833.

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Kitazume, Tomoya, and Jenq Tain Lin. "Synthetic approach to optically pure trifluoromethylated compounds." Journal of Fluorine Chemistry 34, no. 3-4 (January 1987): 461–70. http://dx.doi.org/10.1016/s0022-1139(00)85187-8.

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Overdevest, Pieter E. M., and Albert van der Padt. "ChemInform Abstract: Optically Pure Compounds from Ultrafiltration." ChemInform 31, no. 7 (June 10, 2010): no. http://dx.doi.org/10.1002/chin.200007285.

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Buendia, Julien, Jakob Mottweiler, and Carsten Bolm. "Preparation of Diastereomerically Pure Dilignol Model Compounds." Chemistry - A European Journal 17, no. 49 (November 10, 2011): 13877–82. http://dx.doi.org/10.1002/chem.201101579.

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PYNE, S. G. "ChemInform Abstract: Synthesis of Enantiomerically Pure Compounds." ChemInform 23, no. 11 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199211295.

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Bauer, Sebastian, Steffen Tschirschwitz, Peter Lönnecke, René Frank, Barbara Kirchner, Matthew L. Clarke, and Evamarie Hey-Hawkins. "Enantiomerically Pure Bis(phosphanyl)carbaborane(12) Compounds." European Journal of Inorganic Chemistry 2009, no. 19 (July 2009): 2776–88. http://dx.doi.org/10.1002/ejic.200900304.

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Gharagheizi, Farhad. "Prediction of the Standard Enthalpy of Formation of Pure Compounds Using Molecular Structure." Australian Journal of Chemistry 62, no. 4 (2009): 376. http://dx.doi.org/10.1071/ch08522.

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A predictive approach has been presented to calculate the standard enthalpy of formation of pure compounds based on a quantitative structure–property relationship technique. A large number (1692) of pure compounds were used in this study. A genetic algorithm based on multivariate linear regression was used to subset variable selection. Using the selected molecular descriptors an optimized feed forward neural network was presented to predict the ΔHfo of pure compounds.
10

Vulić, Predrag, Volker Kahlenberg, Christian Gspan, and Radovan Dimitrijević. "Reinvestigation of pure Na-nepheline like compounds obtained from the thermal conversion of zeolite LTA." European Journal of Mineralogy 25, no. 3 (September 13, 2013): 473–78. http://dx.doi.org/10.1127/0935-1221/2013/0025-2293.

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Journal articles Dissertations / Theses Books

Dissertations / Theses on the topic "Pure compounds":

1

Harvey, Ian. "Applications of enzymatic methods to the preparation of enantiomerically pure compounds." Thesis, University of Warwick, 1989. http://wrap.warwick.ac.uk/106588/.

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This thesis describes investigations in the field of biotransformations, concentrating on the mode of action of esterases and lipases, and the application of these systems to the production of enantiomerically pure compounds. The behaviour of pig liver esterase (PLE) in the presence of some commonly use alcohol and ketone cosolvents was examined. Methanol, ethanol and 2-butanone were found to be potent inhibitors of PLE. At low concentrations, acetone accelerated the rata of PLE catalysed hydrolysis, but is also inhibitory at higher concentrations. The effects of alcohols as product inhibitors were examined. This, and other data obtained suggests that the complex kinetics of this enzyme could be explained using the 'Ligand Induced Slow Transition Model" (Ainslie et al., J. Biol. Cham., 1972, 247, 7088). Examination of PLE by gel filtration hplc suggested that the active form of this enzyme may not be trimeric as previously thought. Soma analogous studies were carried out with pig pancreatic lipase. The use of the isosyme-specific inhibitors, eserine and phenylmethylsulfonyl fluoride did not improve the enantiospecificity of the hydrolysis of trans-1,2-diacetoxy-cyclopentane catalysed by PLE. Dimethyl mono-3-cyclobutene-1,2-dicarboxylate was hydrolysed to the corresponding mono-ester by pig liver esterase with high optical purity (56% a.e.) and chemical yield. The mono-ester epimerised during derivatisation mediated by 1,1-carbonyldiimidazole, allowing the preparation of optically pure trans derivatives. Rapid derivatisation allowed the preparation of cis analogues. This was demonstrated by the preparation of both the optically pure cis and trans benzylamide derivatives. Mono-3-Cyclobutane-1.2-dimethanol diacetate was hydrolysed to the corresponding mono-acetate by Pseudomonas fluorescene lipase with high optical purity (>97% a.e. at 0.8 mol-equivalent) and chemical yield. The corresponding (4-phenyl)benzoyl, (4-toluene)sulphonyl and (4-phenylethene-9-yl) derivatives were prepared. The racemic allene diethyl penta-2,3-dismodicate was hydrolysed by pig liver esterase in buffer containing 232 (v/v) acetone. The product, (g)-(-)-ethyl penta-2,3-dismodicate, was produced with 30 – 33% a.e. at 0.3 mol-equivalents. As a demonstration of the development of a hydrolytic resolution procedure, such a method was devised for the preparation of an optically pure halogenated propan-l-el derivative. Pig pancreatic lipase was chosen as the model system. By manipulating the reaction conditions and the acid moiety, the enantiospecificity of the hydrolysis was improved by a minimum of 6.4 times, and possibly by greater than ten-fold.
2

Ellis, Michael Martin. "Formation of pure polycrystalline alpha-alumina fibers from an organo-metallic sol-gel." Thesis, Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/20010.

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3

Carr, Jason A. "The Utilization of Enzymes in the Synthesis and Modification of Natural and NonNatural Compounds: A Chemo-Enzymatic Approach to Enantiomerically Pure Compounds." Scholar Commons, 2004. https://scholarcommons.usf.edu/etd/983.

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The employment of enzymes and whole cells has been important in many industries for centuries. However, it is only in the last 30 years that the use of enzymes for the synthesis of high-value fine chemicals has enjoyed increasing popularity. In fact, esterases and lipases are used almost routinely these days to provide optically active building blocks for the construction of imaginative new routes to chiral target molecules. The major topic of this work describes the utilization of enzymes (namely lipases) in the synthesis and modification of natural and non-natural compounds. Chapter 1 outlines the strengths and weaknesses of the most widely used enzyme systems and a description of a brief summary on the state of the art of biotransformations with special emphasis on the general applicability and reliability of various reaction types is described. Chapter 2 describes the enzymatic resolution of various 3-acetoxy-4-aryl-substituted azetidin-2-ones. Following screening of enzymes, such as Novozym-435, PS-30, PPL and AYS the best conditions were a phosphate buffer with PS-30 as the enzyme. The resulting products were the (3S, 4R)-3-hydroxy-4-aryl-substituted azetidin-2-ones and the unreacted (3R, 4S)-3-acetoxy-4-aryl-substituted azetidin-2-ones. Reactions generally occurred with high conversion and high selectivity. In Chapter 3, the regioselective transesterifications and hydrolysis of peracylated sophorolipid (SL) derivatives catalyzed by lipases was investigated. It was confirmed from the detailed spectral analysis of the products that transesterification failed to furnish any free hydroxyls on the sophorose ring. Instead, transesterification took place on the methyl ester located at the carboxylic end of the 17-hydroxyoctadecenoic acid chain attached to the C-1' position of the sophorose ring. In Chapter 4, the chemo-enzymatic syntheses of enantiomerically pure R and S imperanene from vanillin are described. The key step entails the asymmetrization of a prochiral diol using lipase PS-30. The resulting monoacetate has enantiomeric excesses of >97%. Biocatalysts represent a new class of chiral catalysts useful for a broad range of selective organic transformations. It is stating the obvious to say that biocatalysis is not a panacea for synthetic organic chemistry. However, advances over the past thirty years mean that it would be a serious mistake not to consider the employment of a biocatalyst, in, perhaps, the key step in a sequence of transformations that turn a cheap starting material into an expensive fine chemical.
4

Carr, Jason A. "The utilization of enzymes in the synthesis and modification of natural and non-natural compounds a chemo-enzymatic approach to enantiomerically pure compounds /." [Tampa, Fla.] : University of South Florida, 2004. http://purl.fcla.edu/fcla/etd/SFE0000420.

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Mullins, Paul Eric. "Application of COSMO-SAC to Solid Solubility in Pure and Mixed Solvent Mixtures for Organic Pharmacological Compounds." Thesis, Virginia Tech, 2007. http://hdl.handle.net/10919/31086.

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In this work, we present two open literature databases, the VT-2005 Sigma Profile Database and the VT-2006 Solute Sigma Profile Database, that contain sigma profiles for 1,645 unique compounds. A sigma profile is a molecular-specific distribution of the surface-charge density, which enables the application of solvation-thermodynamic models to predict vapor-liquid and solid-liquid equilibria, and other properties. The VT-2005 Sigma Profile Database generally focuses on solvents and small molecules, while the VT-2006 Solute Sigma Profile Database primarily consists of larger, pharmaceutical-related solutes. We design both of these databases for use with the conductor-like screening model â segment activity coefficient (COSMO-SAC), a liquid-phase activity-coefficient model. The databases contain the necessary information to perform binary and multicomponent VLE and SLE predictions. We offer detailed tutorials and procedures for use with our programs so the reader may also use their own research on our research group website (www.design.che.vt.edu). We validate the VT-2005 Sigma Profile Database by pure component vapor pressure predictions and validate the VT-2006 Solute Sigma Profile Database by solid solubility predictions in pure solvents compared with literature data from multiple sources. Using both databases, we also explore the application of COSMO-SAC to solubility predictions in mixed solvents. This work also studies the effects of conformational isomerism on VLE and SLE property prediction. Finally, we compare COSMO-SAC solubility predictions to solubility predictions by the Non-Random Two-Liquid, Segment Activity Coefficient (NRTL-SAC) model. We find UNIFAC is a more accurate method for predicting VLE behavior than the COSMO-SAC model for many of the systems studied, and that COSMO-SAC predicts solute mole fraction in pure solvents with an average root-mean-squared error (log10(xsol)) of 0.74, excluding outliers, which is greater than the RMS error value of 0.43 using the NRTL-SAC model.


Master of Science
6

Nalla, V. "Synthesis of optically pure pharamaceuticals employing aziridines / epoxides as chiral synthons and development of novel biologically active compounds based on benzopyran -4- ones." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2018. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/5854.

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7

Pradhan, Rajendra Sharad. "Formulation and in vitro release study of poly(DL-lactide) microspheres containing hydrophilic compounds, glycine and its homopeptides." Scholarly Commons, 1992. https://scholarlycommons.pacific.edu/uop_etds/2831.

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In view of current interest in several oligopeptide drugs currently being investigated for controlled implantable delivery, glycine, diglycine, triglycine, tetraglycine and pentaglycine were chosen as model compounds for encapsulation in biodegradable microspheres of DL-polylactide (DL-PLA) by a technique based on oil-in-oil emulsion and the solvent evaporation principle. A DL-polylactide concentration of 10.3% w/w and emulsifier (sorbitan sesquioleate) concentration of 0.3% v/v produced good yields of microspheres with excellent entrapment when processed under following conditions: emulsion time, 1 min; solvent evaporation time, 2 min; internal phase-external phase ratio, 1:7; stirring speed, 1100 rpm; emulsion temperature, 5$\sp\circ$C; and maximum processing temperature, 35$\sp\circ$C. Microspheres prepared as above at four different loadings (2.5, 5.0, 7.5, and 10.0% w/w) were analyzed for morphological and in vitro release characteristics. Analysis of the release data and scanning electron photographs suggested that the release of glycine and its homopeptides from DL-PLA microspheres was most likely by diffusion through the matrix. However, for models having low aqueous solubility, e.g., tetra- and pentaglycine, dissolution played a rate-limiting role. Microspheres of glycine prepared with DL-PLA plasticized with 10% triacetin demonstrated the slowest release, with the first 50% entrapped glycine released over four days and next 25% released at a constant rate over 17 days. This was in sharp contrast to unplasticized microspheres from which glycine was completely leached out in 24 h. Interestingly, while the plasticizer decreased the rate of release of glycine, it appeared to promote the degradation of the polymer DL-PLA.
8

Abubakar, Ibrahim Babangida. "In vitro investigation on synergistic anticancer effects between vitamin E isomers, pure compounds and crude alkaloid plant extracts on human cancerous cells." Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/35974/.

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Anticancer chemotherapeutic treatment using single dose has been limited due to drug resistance and potential metabolic degradation. For instance, high-dose tocotrienols undergo metabolic degradation that limits the availability of therapeutic dose thereby limiting the potency in vivo. Combined treatment of tocotrienols at low dosage has been suggested as alternative to circumventing this limitation. This study was designed to investigate the cytotoxic effects and subsequently the apoptotic mechanisms of individual doses and combined treatments at lower dosages of tocotrienols (delta and gamma), jerantinines (A and B) and extracts (ethanol and alkaloid crude) from leaves and bark of Ficus hispida, Ficus fistulosa and Ficus schwarzii on lung (A549), brain (U87MG) and colon (HT-29) cancer cell lines. Neutral red uptake assay was conducted to evaluate the antiproliferative effect of individual and combined treatments. Staining techniques (histochemical and fluorescence), COMET assay flow cytometric analysis and immunofluorescence were conducted to evaluate cell morphology, DNA damage, cell cycle arrest pattern and antimicrotubule effects. Finally cell and molecular based assays were conducted to investigate the pathways for induction of apoptosis. Cell viability study revealed that alkaloid crude extracts of leaves and bark of F. fistulosa demonstrated the highest potency with IC50 range of 0.96 – 46.81 µg/ml compared to F. schwarzii (8.79 – 107.9 µg/ml) and F. hispida (15.14 – 49.58 µg/ml) on A549, U87MG and HT-29 cells. Both delta- and gamma-tocotrienols induced antiproliferative effects on A549, U87MG and HT-29 cells with IC50 values of 3.12 - 12.40 µg/ml and 3.17 – 16.36 µg/ml, respectively. Potent antiproliferative effects were also evident for jerantinine A (IC50 0.62 – 1.74 µg/ml), jerantinine B (IC50 0.58 – 1.48 µg/ml) and vinblastine (IC50 0.03 – 0.71 µg/ml). However, similar toxic effects on these three compounds were also evident on non-cancerous lung fibroblast (MRC5) cells. The leaf and bark alkaloid crude extracts of F. fistulosa and F. schwarzii were selected for combined treatments. The combined treatment of IC20 doses of F. fistulosa with both delta- and gamma-tocotrienols induced synergistic antiproliferative effects (combination index (CI) < 1) on U87MG and HT-29 with up to 34.7-fold and 4-fold dose reductions for tocotrienols and F. fistulosa extracts, respectively. In contrast, additive (CI = 0.98) or antagonistic effects (CI > 1) were observed for IC20 doses of F. schwarzii extracts combined with delta- and gamma-tocotrienols on HT-29 cells. On the other hand, combined treatments of tocotrienols (delta and gamma) with IC20 doses of jerantinines (A and B) induced synergistic effects (CI < 1) on A549, U87MG and HT-29 cells causing up to 4.48-fold dose reduction of tocotrienols thus reducing toxicity towards MRC5 cells compared to cancer cells. Further morphological and DNA damage assessment focusing on tocotrienols (delta and gamma), jerantinines (A and B) and combined low-dose treatments revealed anticancer features including cell shrinkage, nuclear chromatin condensation and fragmentation, membrane blebbing, apoptotic bodies and induction of predominantly double stranded DNA breaks. Cell cycle analysis demonstrated the induction of G0/G1 and G2/M cell cycle arrests by tocotrienols (delta and gamma) and jerantinines (A and B), respectively on U87MG, A549 and HT-29 cells. Meanwhile, G2/M (A549) and G0/G1 (U87MG and HT-29) cell cycle arrests were evident for combined low-dose treatments of tocotrienols (delta and gamma) with IC20 doses of jerantinines (A and B). Jerantinines A and B and combined low-dose treatments with tocotrienols (delta and gamma) caused disruption of microtubule networks and induction of caspase 8-, 9- and 3-mediated apoptosis with caspase-independent growth inhibition evidenced in the presence of caspase inhibitors on U87MG, A549 and HT-29 cells. In contrast, although treatments of tocotrienols (delta and gamma) alone caused similar apoptotic features as those of combined, disruption of microtubule networks were not characterized on these three cancer cell lines. Further mechanistic study on U87MG cells revealed that the apoptosis triggered by individual doses of tocotrienols (delta and gamma) involved the activation of TRAIL and Bid as well as the release of cytochrome C, thus confirming the recruitment of the death receptor and mitochondria-mediated pathways. On the other hand, individual doses of jerantinines (A and B) and combined low-dose treatments with tocotrienols resulted in the activation of TRAIL, FAS, p53 and Bid, as well as the release of cytochrome C. The activation of both death receptors, p53 and microtubule disruption by combined low-dose treatments demonstrates an improved mechanism of action comparing to individual doses of tocotrienols and jerantinines. In addition, the combined low-dose treatments also caused a reduction of required potent doses thereby minimizing the toxicity of jerantinines (A and B) towards the non-cancerous MRC5 cells. In conclusion, this research has presented valuable combined treatment candidates which are warranted for further investigations as future chemotherapeutic agents against cancers.
9

Eckard, Phyllis R. "The Investigation of Primary and Secondary Modifiers in the Extraction and Separation of Neutral and Ionic Pharmaceutical Compounds with Pure and Modified Carbon Dioxide." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/30500.

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A successful supercritical fluid extraction method includes removal of the analyte from the matrix into the bulk fluid as well as trapping or concentration of the analyte prior to analysis. In the first phase of this research, the trapping capacities of three solid-phase traps (glass beads, 50/50 (w/w) glass beads/octadecylsilica), 50/50 (w/w) Porapak Q®/glass beads) were determined as a function of trap composition for a mixture of components varying in polarity and volatility. The Porapak Q®/glass beads mixture was found to be the most successful solidphase investigated exhibiting the highest trapping capacity. The use of the Porapak Q®/glass beads as a solid-phase trap was investigated in later extraction studies in this dissertation. The extraction of highly polar, multifunctional analytes may not be completely successful with modified carbon dioxide, therefore, a secondary modifier (i.e. additive) may be added directly to the extraction fluid in hopes of improving the recoveries. In the second phase of this research, the effect of secondary modifiers in the subcritical fluid extraction of lovastatin from in-house prepared tablet powder mixtures and MEVACOR® tablets was investigated. The effect of in-line methanol-modifier percentage, additive type (acidic, basic, neutral) to the in-line methanol, and additive concentration on the extraction efficiency were examined. The extraction recoveries of lovastatin from MEVACOR® tablets were shown to be highly dependent on methanol concentration and additive type. Isopropylamine was shown to be the most successful additive investigated. An optimized and reproducible extraction method was developed. The extraction of ionic compounds with carbon dioxide may be difficult due to the high polarity of the compounds. In the third phase of this research, the addition of ion-pairing additives to the matrix in hopes of forming an ion-pair complex of reduced analyte polarity was investigated. Therefore, a screening study consisting of a fractional-factorial design was performed in order to identify the factors which contribute most to the recovery of an anionic species, triphenylphosphinetrisulfonate (TPPTS), from a spiked-sand surface employing supercritical fluid extraction with carbon dioxide. The experimental parameters investigated were: type of ion-pairing additive (i.e. tetralkylammonium hydrogen sulfates) and its concentration, carbon dioxide density, extraction temperature, static extraction time, CO₂ mass used, liquid CO₂ flow rate, and the volume of methanol spiked into the matrix prior to extraction. Of the eight factors investigated, four factors were identified as significantly affecting the recovery of the anionic species. They were: 1) ion-pairing reagent added to the spiked sand surface and its concentration; 2) static extraction time; and 3) volume of methanol present in the extraction vessel. The experimental parameters and settings identified as influential by the statistical approach were later shown in concert to yield 100% recovery of TPPTS from the spiked-sand. In the fourth phase, the extraction of a cationic species, pseudoephedrine hydrochloride, from spiked-sand and Suphedrine tablets, with pure and methanol-modified CO₂ was examined. Once the extraction was shown to feasible, several strategies were compared in terms of their effectiveness in enhancing the analyte's extractability. The first strategy involved the addition of ion-pairing additives. Several sodium salts of alkylsulfonic acids varying in lipophilicity and concentration were investigated. The addition of 1-heptanesulfonic acid, sodium salt, in methanol, in a 5:1 mole ratio of reagent to analyte was shown to be the most useful in recovering the drug from the spiked-sand. The second strategy considered the influence of acids and bases and other modifier compositions such as a methanol/water mixture with or without 1-heptanesulfonic acid, sodium salt, on the pseudoephedrine recovery. The recoveries obtained from the drug spiked-sand were shown to comparable in the presence of a methanol/water solution, a tetrabutylammonium hydroxide in methanol solution, and a methanol solution with 1-heptanesulfonic acid, sodium salt. Next the extraction of pseudoephedrine hydrochloride from Suphedrine tablets was performed with pure and modified CO₂. Similar to the sand-spike studies, the effect of the addition of the ion-pairing reagent and other in-cell modifiers were examined. Once again, the recoveries obtained when the matrix was in the presence of a methanol/water mixture and a methanol solution containing 1-heptanesulfonic acid, sodium salt were similar. Finally, the identity of the extracted analyte was determined via IR analyses, and it was shown that pseudoephedrine hydrochloride was indeed extractable from the tablets with in-line modified CO₂ in the absence of any in-cell modifier. In the last phase of this research, a supercritical fluid chromatographic separation with evaporative light scattering detection was developed for the separation of five phospholipids varying in polarity and ionic characteristics. Several parameters were investigated and shown to be influential in the separation. They were: 1) stationary phase composition, 2) addition of an acidic additive and its concentration, 3) mobile phase ramp rate, and 4) column outlet pressure.
Ph. D.
10

Vangani, Saroj. "Development of an in vitro dissolution model to predict the in vivo behavior of poorly soluble compounds." Scholarly Commons, 2010. https://scholarlycommons.pacific.edu/uop_etds/2412.

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One of the challenges of biopharmaceutics research is correlating in vitro drug release information with the in vivo drug profiles often known as in vitro-in vivo correlations (IVIVC). These have huge cost savings in pharmaceutical industry. This dissertation describes the development of a novel in vitro dissolution model that has been designed to evaluate the in vitro release of poorly water-soluble model compounds so as to predict their in vivo behavior. The flow through apparatus (USP 4) has been coupled with the compendial dissolution apparatus (USP 2). A bi-phasic dissolution medium has been used to achieve sink conditions. The dissolved drug from the aqueous phase is continuously extracted into the organic phase of the biphasic dissolution medium, mimicking the dynamic process of in vivo absorption. The model can successfully discriminate between the bioequivalent and non-bioequivalent formulations and can be used to establish IVIVC. It was concluded that the model will serve as a surrogate for bioequivalence studies and to support biowaivers.
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Books on the topic "Pure compounds":

1

Smith, Buford D. Thermodynamic data for pure compounds. Amsterdam: Elsevier, 1986.

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Smith, Buford D. Thermodynamic data for pure compounds. Amsterdam: Elsevier, 1986.

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Daubert, T. E. Data compilation tables of properties of pure compounds. New York, N.Y. (345 E. 47th St., New York 10017): Design Institute for Physical Property Data, American Institute of Chemical Engineers, 1985.

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Clifton, Farrell, Williams Tracie, and Superfund Innovative Technology Evaluation Program (U.S.), eds. Electro-pure alternating current electrocoagulation. Cincinnati, OH: U.S. Environmental Protection Agency, Superfund Innovative Technology Evaluation, 1993.

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Clifton, Farrell, Williams Tracie, and Superfund Innovative Technology Evaluation Program (U.S.), eds. Electro-pure alternating current electrocoagulation. Cincinnati, OH: U.S. Environmental Protection Agency, Superfund Innovative Technology Evaluation, 1993.

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Clifton, Farrell, Williams Tracie, and Superfund Innovative Technology Evaluation Program (U.S.), eds. Electro-pure alternating current electrocoagulation. Cincinnati, OH: U.S. Environmental Protection Agency, Superfund Innovative Technology Evaluation, 1993.

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Harvey, Ian. Applications of enzymatic methods to the preparation of enantiomerically pure compounds. [s.l.]: typescript, 1989.

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Horvath, A. L. Molecular design: Chemical structure generation from the properties of pure organic compounds. Amsterdam: Elsevier, 1992.

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Macaev, Fliur. Natural [alpha]-pinenes, carvones, 2- and 3-carenes as source of enantio-pure compounds. Chișinău: Academy of Sciences of Moldova, Institute of Chemistry, 2011.

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ʻUthmān, ʻĀdil ʻAlī. Madkhal ilā taṣnīf wa-tasmīyat al-murakkabāt al-ʻuḍwīyah ḥasab niẓām IUPAC. al-Jazāʼir: Dār Hūmah lil-Ṭibāʻah wa-al-Nashr, 2000.

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Book chapters on the topic "Pure compounds":

1

Brown, Herbert C., Prabhakar K. Jadhav, and Bakthan Singram. "Enantiomerically Pure Compounds via Chiral Organoboranes." In Modern Synthetic Methods, 307–56. Berlin, Heidelberg: Springer Berlin Heidelberg, 1986. http://dx.doi.org/10.1007/978-3-642-82805-8_6.

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Benjelloun, Driss, Jean-Pierre Bonnet, and Marc Onillon. "Anisotropy of Electrical Properties in Pure and Doped αFe2O3." In Transport in Nonstoichiometric Compounds, 51–60. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4613-2519-2_5.

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Nag, Ahindra. "Enantiomerically Pure Compounds by Enantioselective Synthetic Chiral Metal Complexes." In Asymmetric Synthesis of Drugs and Natural Products, 75–131. Boca Raton : CRC Press, 2018.: CRC Press, 2018. http://dx.doi.org/10.9774/gleaf.9781315302317-3.

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Asih, Retno, Malik Anjelh Baqiya, Yoyok Cahyono, and Darminto. "Biomass-derived Carbon Compounds and their Potential Application for Electronic and Magnetic Materials." In Pure and Functionalized Carbon Based Nanomaterials, 80–101. Boca Raton : CRC Press, Taylor and Francis Group, [2020] | “CRC Press is an imprint of the Taylor & Francis Group, an informa business.”: CRC Press, 2020. http://dx.doi.org/10.1201/9781351032308-4.

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Ribeiro, Sidarta. "Whole Organisms or Pure Compounds? Entourage Effect Versus Drug Specificity." In Plant Medicines, Healing and Psychedelic Science, 133–49. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-76720-8_8.

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Zanoni, R. "X-Ray Photoelectron Spectroscopy Applied to Pure and Supported Molecular Metal Clusters." In Physics and Chemistry of Metal Cluster Compounds, 159–82. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-015-1294-7_5.

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Hoppe, Dieter. "Synthesis of Enantiomerically Pure Unnatural Compounds Via Non-Biomimetic Homoaldol Reactions." In Enzymes as Catalysts in Organic Synthesis, 177–98. Dordrecht: Springer Netherlands, 1986. http://dx.doi.org/10.1007/978-94-009-4686-6_11.

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Elvevold, Kjetil, Ingelin Kyrrestad, and Bård Smedsrød. "Protocol for Isolation and Culture of Mouse Hepatocytes (HCs), Kupffer Cells (KCs), and Liver Sinusoidal Endothelial Cells (LSECs) in Analyses of Hepatic Drug Distribution." In Methods in Molecular Biology, 385–402. New York, NY: Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2010-6_27.

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AbstractDevelopment of the new generation of drugs (e.g., oligo- and polynucleotides administered intravascularly either as free compounds or as nano-formulations) frequently encounters major challenges such as lack of control of targeting and/or delivery. Uncontrolled or unwanted clearance by the liver is a well-known and particularly important hurdle in this respect. Hence, reliable techniques are needed to identify the type(s) of liver cells, receptors, and metabolic mechanisms that are responsible for unwanted clearance of these compounds.We describe here a method for the isolation and culture of the major cell types from mouseliver: hepatocytes (HCs), Kupffer cells (KCs), and liver sinusoidal endothelial cells (LSECs). The presently described protocol employs perfusion of the liver with a collagenase-based enzyme preparation to effectively transform the intact liver to a single cell suspension. From this initial cell suspension HCs are isolated by specified centrifugation schemes, yielding highly pure HC preparations, and KCs and LSECs are isolated by employing magnetic-activated cell sorting (MACS). The MACS protocol makes use of magnetic microbeads conjugated with specific antibodies that bind unique surface antigens on either KCs or LSECs. In this way the two cell types are specifically and separately pulled out of the initial liver cell suspension by applying a magnetic field, resulting in high purity, yield, and viability of the two cell types, allowing functional studies of the cells.If the drug compound in question is to be studied with respect to liver cell distribution of intravascularly administered drug compounds the isolated cells can be analyzed directly after isolation. Detailed studies of receptor-ligand interactions and/or dynamics of intracellular metabolism of the compound can be conducted in primary surface cultures of HCs, LSECs, and KCs established by seeding the isolated cells on specified growth substrates.
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D’Haen, Jan, Marc D’Olieslaeger, Luc Schepper, and Lambert M. Stals. "Quantitative Analysis of the Compound Layer of Plasma Nitrided Pure Iron." In Microbeam and Nanobeam Analysis, 271–77. Vienna: Springer Vienna, 1996. http://dx.doi.org/10.1007/978-3-7091-6555-3_18.

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Sukh, Dev, and Koul Opender. "Pure Compounds." In Insecticides of Natural Origin, 25–356. Routledge, 2017. http://dx.doi.org/10.1201/9780203750759-2.

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Conference papers on the topic "Pure compounds":

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Fadil MOUSA, Enaam, and Ibtissam Khalifa JASSIM. "SYNTHESIS ,CHARACTERIZATION AND BIOLOGICAL ACTIVITY STUDY OF SOME HETEROCYCLIC COMPOUNDS." In IV.International Scientific Congress of Pure,Appliedand Technological Sciences. Rimar Academy, 2022. http://dx.doi.org/10.47832/minarcongress4-18.

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Heterocycles are an important class of organic compounds because of their applications in medicines and industrial fields. Therefore our study included preparation of these compound such as oxazepine and quinazoline rings, which were prepared through two steps: The first step included the reaction of the Schiff bases derived from sulfamethaxazole (1-4) with each of phthalic anhydride and 3- nitrophthalic anhydride for the preparation of oxazepines (5-12) .While the second step included the preparation of quinazoline compounds (13-16) from the reaction of Schiff bases (1-4) with anthranilic acid using dry benzene as a medium and solvent for the reaction. All prepared compounds were characterized by using infrared,proton- nuclear magnetic resonance, mass techniques and melting points, and their purity was determined by thin layer chromatography technique also screened the biological activity of some of these prepared compounds by using two types of bacteria Gram-positive and negative . The results showed that these compounds have a good inhibition against these organisms
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MOHSIN, Doaa Hadi, and Zahraa Hameed KAMIL. "SYNTHESIS AND CHARACTERIZATION OF SOME NEW 1,3-OXAZEPINE COMPOUNDS." In III.International Scientific Congress of Pure,Appliedand Technological Sciences. Rimar Academy, 2021. http://dx.doi.org/10.47832/minarcongress3-3.

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In this study, bis imines were synthesized by reacting aldehyde with diamine in the presence of chloroformat (55-60˚C). In moderate yield (78-82) %, and then used in the preparation of 1, 3-Oxazepine compounds by reacting with phathalic anhydridein Benzene at (80-85 ˚C). In moderate yield (83-88) %.These vehicles have been verified using(FT-IR). Key words: Characterization, Compound, Oxazepine.
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A. JASIM, Nidaa. "THEORETICAL STUDY OF THE PHYSICAL PROPERTIES AND THERMODYNAMIC FUNCTIONS OF ASPIRIN USING QUANTUM MECHANICS CALCULATION (PARAMETRIC METHOD 3)." In VII. INTERNATIONAL SCIENTIFIC CONGRESSOF PURE,APPLIEDANDTECHNOLOGICAL SCIENCES. Rimar Academy, 2023. http://dx.doi.org/10.47832/minarcongress7-14.

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In this study, the theoretical quantum programs were relied upon to study some of the physical and radiodynamic properties, in addition to the spectral study of the aspirin compound. PM3 quantum chemistry methods and Gaussian 09 W program were applied to the calculation of the balanced dimentions (bond lengths, length angles in Angstrom) , The thermodynamic functions ( E0 , H0 ,A0 ,S0 ,CV ) was calculated of compounds studied and also some physical properties (EHOMO , ELUMO , ∆𝐸 , IP ) was also calculated. This study is important to reach additional theoretical information about acetylsalicylic acid (aspirin) using theoretical chemistry programs and compare it in the future with salicylic acid derivatives classified as analgesics to reach the best drugs on the other hand biological on the body.
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Lin, Wei-Ming, T. D. Lin, Chao-Lung Hwang, and Yaw-Nan Peng. "Heat of Hydration of Pure Cement Compounds with Steam." In Fifth International Conference on Space. Reston, VA: American Society of Civil Engineers, 1996. http://dx.doi.org/10.1061/40177(207)81.

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J. AJEENA, Saba, Zainab A. JABARAH, and Suhayla khalied MOHAMMED. "EVALUATION THE ANTIOXIDANT ACTIVITY OF ALEO VERA LEAVES EXTRACTS." In VII. INTERNATIONAL SCIENTIFIC CONGRESSOF PURE,APPLIEDANDTECHNOLOGICAL SCIENCES. Rimar Academy, 2023. http://dx.doi.org/10.47832/minarcongress7-8.

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Certain chemical compounds, such as biologically active molecules, can be produced and found in high concentrations in plants. Aloe vera plant consists mainly of more than 90% water and many chemical compounds, such as polysaccharides, due to its ability to adapt to desert conditions and environments. More than 200 nutritional substances were found to be exist in aloe vera, including vitamins, enzymes, minerals, polysaccharides, lignin, antioxidants and amino acids. flavonoids and phenols, among the important compounds, play an important and vital role as antioxidants by their function as free radicals’ scavengers. The current research is aiming to investigate the value of total polyphenols , flavonoids and antioxidant activities of magnetized water, non-magnetized water and alcoholic extracts of fresh Aloe Vera leaves .The study showed that the extracts of ethanol and magnetized water are much better than non-magnetized water.
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NASER, Estabraq H., and Haifaa R. ALANSARI. "COMPARATIVE STUDY OF THREE SEQUENTIAL EXTRACTION PROCEDURES FOR SECONDARY METABOLITES IN SEEDS OF PORTULACA OLERACEA PLANT BY GC.MS TECHNIQUE." In IV.International Scientific Congress of Pure,Appliedand Technological Sciences. Rimar Academy, 2022. http://dx.doi.org/10.47832/minarcongress4-30.

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Secondary metabolites referred to as phytochemical compounds that have importance in the recovery of many ailments. In order to identify these compounds and get their benefits, they must be identified and isolated from their parent plant; one of them is Portulaca oleracea that is belongs to portulacaceae family. The seeds are extracted by three different sequential extraction methods including petroleum ether, Ethylacetate, and methanol in way based on gradual increasing solvent polarity. The quantification and identification of the compounds were carried out by gas chromatography mass detection apparatus. The result shown that these seeds contain many secondary metabolites like flavonoids, alkaloids, saponins, steroids and phenolic compounds. The GC-MS analysis of the seeds extracts showed the presence of many important compunds such as, trans-geranylgeraniol, tetracosanoic acid, trans-farnesol, digitoxin, vitamin E, estrol and cis-6-octadecenoic acid in high percent in addition to little percent distributed between β-sitosterol, gitoxigenin, (+)-α-tocopherol, camphene, hexadecane, δ-elemene, 3- methoxybenzyl alcohol, ecgonine, (-)-myrtenol, cholecalciferol, 9cis-retinal, limonene-6-ol,pivalate, p-cymene, γ-terpinene, humulene, patulin, 1,12tridecadiene, isopropyl linoleate, pentadecane, elaidic acid, ascorbic acid,permethyl-, dodecanedioic acid, carvedilol, heptadecanoic acid, linolenic acid, kampferol-3,4'-dimethyl ether, and scopoletin, it is important to mention that these compounds can be utilized in the treatment of many diseases as single drug. Key words: Digitoxin, Vitamin E, Portulacaceae, GC.MS, Phytochemical Screening.
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Hamid Ahmed, Maysaa, and Asmaa Obaid Ismeel. "Using Silver Nanoparticles to Increase Some Glycosidic Compounds of Stevia Rebaudiana in Vitro." In X INTERNATIONAL CONGRESS OF PURE AND APPLIED TECHNOLOGICAL SCIENCES. Rimar Academy, 2023. http://dx.doi.org/10.47832/minarcongress10-7.

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This experiment was objected to increase some Glycosides active compounds production in Stevia rebaudiana seedlings through plant seeds treatment with different concentrations of silver nanoparticles that diagnosed and characterized using AFM technique. This research was implemented at plant tissue culture laboratory of College of biotechnology - Al Nahrain University, throughout the period of 2022 and 2023. The experiment designed factorial within CRD using three expermentse and ten replicates. Sodium hypochlorite concentration (S1, S2, S3, S4) (0.0, 1, 2, 3%) represented the first experment, treatment duration time (T1, T2, T3) (5, 10, 15min) represented experiment 2, silver nanoparticles concentrations (C1, C2, C3, C4) (0, 10, 20, 30 mg.l-1) in MS media, represented experiment 3. Results showed that the contamination rate of the selected S. rebaudiana explant reduced and registered at at 10 and 15min in 3% sodium hypochlorite. The results also showed that there were a significant increase in the shoots numbers in 30 mg.l-1 AgNPs that reach the highest in terms of shoots numbers, the significant increasing of shoot length within the10 mg.l-1 enrolment 14.5cm then decreased in both concentrations 20, 30 mg.l-1 , seedlings dry weight significantly raised up to 20 mg.l-1 , while the seedlings dry weight also significantly droped in 30 mg.l-1 AgNPs., all the analyzed Glycosides compounds using HPLC device as Rubsoside , Dulcoside ,Stevioside concentrations were significantly increased in 20 and 30 mg.l-1 AgNPs, in comparsion to the control
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Hostnik, Gregor, Anja Petek, Sara Štumpf, Franjo Frešer, Zala Kolenc, Matej Keber, Jelena Tošović, and Urban Bren. "Elucidating Health-Enhancing Properties of Natural Products: A Journey from Extract Isolation to Quantum Mechanics (QM) Calculations." In 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.261h.

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Natural extracts are a promising source of compounds with health-enhancing properties. However, the challenge lies in understanding the relationships between the composition of extracts, and the connection between the structure and activity of its constituents, given that the extracts are a complex mixture. Typically, researchers adopt two main methods to tackle this: experimental examination of the biological activity of the extracts and computational chemistry to obtain insights into the properties of the molecules. There are, however, inherent challenges in drawing comparisons between the results of these methods, particularly because of the potential antagonistic and synergistic effects of compounds present within the natural extracts. This task is significantly simplified when pure compounds are used for experimental work. This study exemplifies the process of isolating pure compounds from hop and chestnut wood extracts using preparative High-Performance Liquid Chromatography (HPLC). The pKa values, chelation ability and antibacterial activity of isolated compounds were examined experimentally. Moreover, the experimental results were further elucidated with computational findings, an approach made possible using pure compounds. This comprehensive approach significantly enhances our understanding of these natural compounds.
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Azeez, Hashim, and Bana Abdulrahman. "Synthesis and Spectroscopic Characterization of a New Series of Thiazolidin-4-One Compounds from Heterocyclic Schiff Bases." In 2018 International Conference on Pure and Applied Science. Koya University, 2018. http://dx.doi.org/10.14500/icpas2018.ach77.

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Wang, Ziwen. "Ginger extract compounds in treatment of ischemic stroke: Mechanisms and applications." In 7TH INTERNATIONAL CONFERENCE ON MATHEMATICS: PURE, APPLIED AND COMPUTATION: Mathematics of Quantum Computing. AIP Publishing, 2022. http://dx.doi.org/10.1063/5.0111659.

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Reports on the topic "Pure compounds":

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Phillips, Donald A., Yitzhak Spiegel, and Howard Ferris. Optimizing nematode management by defining natural chemical bases of behavior. United States Department of Agriculture, November 2006. http://dx.doi.org/10.32747/2006.7587234.bard.

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This project was based on the hypothesis that nematodes interacting with plants as either parasites or beneficial saprophytes are attracted to their host by natural products. This concept was supported by numerous observations that parasitic nematodes are attracted to root exudates. Our overall goal was to identify nematode sensory compounds from root exudates and to use that information for reducing nematicide applications. We applied skills of the investigators to achieve three specific objectives: 1) Identify nematode behavioral cues (e.g., attractants or repellents) in root exudates; 2) Identify new natural nematicidal compounds; and 3) Combine a natural attractant and a nematicide into a nematode trap. Because saprophytic nematodes benefit plants by mineralizing organic matter, we sought compounds attractive primarily to parasitic nematodes. The project was constructed on several complementary foundations. First, data from Dr. Spiegel’s lab showed that under aseptic conditions Ditylenchus dipsaci, a parasite on onion, is attracted to certain fractions of onion root exudates. Second, PI Phillips had a sizeable collection of natural plant products he had identified from previous work on Rhizobium-legume interactions, which could be tested “off the shelf”. Third, Dr. Ferris had access to aseptic and natural populations of various saprophytic and parasitic nematodes. The project focused on five nematode species: D.dipsaci, Heterodera avenae, and Tylenchulussemipenetransat ARO, and Meloidogyne javanicand Caenorhabditis elegans at UCD. Ten pure plant compounds, mostly flavonoids, were tested on the various nematode species using six different assay systems. Results obtained with assorted test systems and by various scientists in the same test systems were essentially irreproducible. Many convincing, Many convincing, i.e. statistically significant, results in one system or with one investigator could not be repeated with other assays or different people. A recent report from others found that these compounds, plus another 30, were inactive as attractants in three additional parasitic nematode species (Wuyts et al. Nematology 8:89- 101, 2006). Assays designed to test the hypothesis that several compounds together are required to attract nematodes have thus far failed to find a reproducibly active combination. In contrast to results using pure plant compounds, complex unfractionated exudates from aseptic onion root reproducibly attracted D. dipsaci in both the ARO and UCD labs. Onion root exudate collection, separation into HPLC fractions, assays using D. dipsaci and MS-MS experiments proceeded collaboratively between ARO and UCD without any definitive identification of an active compound. The final active fraction contained two major molecules and traces of several other compounds. In the end, analytical studies were limited by the amount of onion root exudate and the complexity of the purification process. These tests showed that aseptic plant roots release attractant molecules, but whether nematodes influence that release, as insects trigger release of attractants from plants, is unknown. Related experiments showed that the saprophyte C. elegans stimulates its prey, Pseudomonas bacteria, to increase production of 2, 4-diacetylphloroglucinol (DAPG) a compound that promotes amino acid exudation by plant roots. It is thus possible that saprophytic nematodes are attracted primarily to their bacterial or fungal prey and secondarily to effects of those microorganisms on root exudation. These observations offer promising avenues for understanding root-zone interactions, but no direct routes to controlling nematodes in agriculture were evident. Extracts from two plant sources, Chrysanthemum coronarium and Sequoia sempervirens, showed nematicidal activity at ARO and UCD, respectively. Attempts to purify an active compound from S. sempervirens failed, but preliminary results from C. coronarium are judged to form a potential basis for further work at ARO. These results highlight the problems of studying complex movement patterns in sentient organisms like nematodes and the issues associated with natural product isolation from complex mixtures. Those two difficulties combined with complications now associated with obtaining US visas, slowed and ultimately limited progress on this project. As a result, US investigators expended only 65% of the $207,400 originally planned for this project. The Israeli side of the project advanced more directly toward its scientific goals and lists its expenditures in the customary financial report.
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Becher, Julie, Samuel Beal, Susan Taylor, Katerina Dontsova, and Dean Wilcox. Photo-transformation of aqueous nitroguanidine and 3-nitro-1,2,4-triazol-5-one : emerging munitions compounds. Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41743.

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Two major components of insensitive munition formulations, nitroguanidine (NQ) and 3-nitro-1,2,4-triazol-5-one (NTO), are highly water soluble and therefore likely to photo-transform while in solution in the environment. The ecotoxicities of NQ and NTO solutions are known to increase with UV exposure, but a detailed accounting of aqueous degradation rates, products, and pathways under different exposure wavelengths is currently lacking. We irradiated aqueous solutions of NQ and NTO over a 32-h period at three ultraviolet wavelengths and analyzed their degradation rates and transformation products. NQ was completely degraded by 30 min at 254 nm and by 4 h at 300 nm, but it was only 10% degraded after 32 h at 350 nm. Mass recoveries of NQ and its transformation products were >80% for all three wavelengths. NTO degradation was greatest at 300 nm with 3% remaining after 32 h, followed by 254 nm (7% remaining) and 350 nm (20% remaining). Mass recoveries of NTO and its transformation products were high for the first 8 h but decreased to 22–48% by 32 h. Environmental half-lives of NQ and NTO in pure water were estimated as 4 and 6 days, respectively. We propose photo-degradation pathways for NQ and NTO supported by observed and quantified degradation products and changes in solution pH.
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Steele, W. V., R. D. Chirico, A. Nguyen, I. A. Hossenlopp, and N. K. Smith. Determination of some pure compound ideal-gas enthalpies of formation. Office of Scientific and Technical Information (OSTI), June 1989. http://dx.doi.org/10.2172/6020818.

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Altstein, Miriam, and Ronald Nachman. Rationally designed insect neuropeptide agonists and antagonists: application for the characterization of the pyrokinin/Pban mechanisms of action in insects. United States Department of Agriculture, October 2006. http://dx.doi.org/10.32747/2006.7587235.bard.

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The general objective of this BARD project focused on rationally designed insect neuropeptide (NP) agonists and antagonists, their application for the characterization of the mechanisms of action of the pyrokinin/PBAN (PK-PBAN) family and the development of biostable, bioavailable versions that can provide the basis for development of novel, environmentally-friendly pest insect control agents. The specific objectives of the study, as originally proposed, were to: (i) Test stimulatory potencies of rationally designed backbone cyclic (BBC) peptides on pheromonotropic, melanotropic, myotropic and pupariation activities; (ii) Test the inhibitory potencies of the BBC compounds on the above activities evoked either by synthetic peptides (PBAN, LPK, myotropin and pheromonotropin) or by the natural endogenous mechanism; (iii) Determine the bioavailability of the most potent BBC compounds that will be found in (ii); (iv) Design, synthesize and examine novel PK/PBAN analogs with enhanced bioavailability and receptor binding; (v) Design and synthesize ‘magic bullet’ analogs and examine their ability to selectively kill cells expressing the PK/PBAN receptor. To achieve these goals the agonistic and antagonistic activities/properties of rationally designed linear and BBC neuropeptide (NP) were thoroughly studied and the information obtained was further used for the design and synthesis of improved compounds toward the design of an insecticide prototype. The study revealed important information on the structure activity relationship (SAR) of agonistic/antagonistic peptides, including definitive identification of the orientation of the Pro residue as trans for agonist activity in 4 PK/PBANbioassays (pheromonotropic, pupariation, melanotropic, & hindgut contractile) and a PK-related CAP₂b bioassay (diuretic); indications that led to the identification of a novel scaffold to develop biostbiostable, bioavailable peptidomimetic PK/PBANagonists/antagonists. The work led to the development of an arsenal of PK/PBAN antagonists with a variety of selectivity profiles; whether between different PKbioassays, or within the same bioassay between different natural elicitors. Examples include selective and non-selective BBC and novel amphiphilic PK pheromonotropic and melanotropic antagonists some of which are capable of penetrating the moth cuticle in efficacious quantities. One of the latter analog group demonstrated unprecedented versatility in its ability to antagonize a broad spectrum of pheromonotropic elicitors. A novel, transPro mimetic motif was proposed & used to develop a strong, selective PK agonist of the melanotropic bioassay in moths. The first antagonist (pure) of PK-related CAP₂b diuresis in flies was developed using a cisPro mimetic motif; an indication that while a transPro orientation is associated with receptor agonism, a cisPro orientation is linked with an antagonist interaction. A novel, biostablePK analog, incorporating β-amino acids at key peptidase-susceptible sites, exhibited in vivo pheromonotropic activity that by far exceeded that of PBAN when applied topically. Direct analysis of neural tissue by state-of-the-art MALDI-TOF/TOF mass spectrometry was used to identify specific PK/PK-related peptides native to eight arthropod pest species [house (M. domestica), stable (S. calcitrans), horn (H. irritans) & flesh (N. bullata) flies; Southern cattle fever tick (B. microplus), European tick (I. ricinus), yellow fever mosquito (A. aegypti), & Southern Green Stink Bug (N. viridula)]; including the unprecedented identification of mass-identical Leu/Ile residues and the first identification of NPs from a tick or the CNS of Hemiptera. Evidence was obtained for the selection of Neb-PK-2 as the primary pupariation factor of the flesh fly (N. bullata) among native PK/PK-related candidates. The peptidomic techniques were also used to map the location of PK/PK-related NP in the nervous system of the model fly D. melanogaster. Knowledge of specific PK sequences can aid in the future design of species specific (or non-specific) NP agonists/antagonists. In addition, the study led to the first cloning of a PK/PBAN receptor from insect larvae (S. littoralis), providing the basis for SAR analysis for the future design of 2ⁿᵈgeneration selective and/or nonselective agonists/antagonists. Development of a microplate ligand binding assay using the PK/PBAN pheromone gland receptor was also carried out. The assay will enable screening, including high throughput, of various libraries (chemical, molecular & natural product) for the discovery of receptor specific agonists/antagonists. In summary, the body of work achieves several key milestones and brings us significantly closer to the development of novel, environmentally friendly pest insect management agents based on insect PK/PBANNPs capable of disrupting critical NP-regulated functions.

To the bibliography