WorldWideScience

Sample records for biology organic chemistry

  1. Organic chemistry and biology of the interstellar medium

    Science.gov (United States)

    Sagan, C.

    1973-01-01

    Interstellar organic chemistry is discussed as the field of study emerging from the discovery of microwave lines of formaldehyde and of hydrogen cyanide in the interstellar medium. The reliability of molecular identifications and comparisons of interstellar and cometary compounds are considered, along with the degradational origin of simple organics. It is pointed out that the contribution of interstellar organic chemistry to problems in biology is not substantive but analogical. The interstellar medium reveals the operation of chemical processes which, on earth and perhaps on vast numbers of planets throughout the universe, led to the origin of life, but the actual molecules of the interstellar medium are unlikely to play any significant biological role.

  2. Synthetic biology: lessons from the history of synthetic organic chemistry.

    Science.gov (United States)

    Yeh, Brian J; Lim, Wendell A

    2007-09-01

    The mid-nineteenth century saw the development of a radical new direction in chemistry: instead of simply analyzing existing molecules, chemists began to synthesize them--including molecules that did not exist in nature. The combination of this new synthetic approach with more traditional analytical approaches revolutionized chemistry, leading to a deep understanding of the fundamental principles of chemical structure and reactivity and to the emergence of the modern pharmaceutical and chemical industries. The history of synthetic chemistry offers a possible roadmap for the development and impact of synthetic biology, a nascent field in which the goal is to build novel biological systems.

  3. Organic chemistry

    International Nuclear Information System (INIS)

    2003-08-01

    This book with sixteen chapter explains organic chemistry on linkage isomerism such as alkane, cycloalkane, alkene, aromatic compounds, stereo selective isomerization, aromatic compounds, stereo selective isomerization, organic compounds, stereo selective isomerization, organic halogen compound, alcohol, ether, aldehyde and ketone, carboxylic acid, dicarboxylic acid, fat and detergent, amino, carbohydrate, amino acid and protein, nucleotide and nucleic acid and spectroscopy, a polymer and medical chemistry. Each chapter has introduction structure and characteristic and using of organic chemistry.

  4. Organic chemistry and biology: chemical biology through the eyes of collaboration.

    Science.gov (United States)

    Hruby, Victor J

    2009-12-18

    From a scientific perspective, efforts to understand biology including what constitutes health and disease has become a chemical problem. However, chemists and biologists "see" the problems of understanding biology from different perspectives, and this has retarded progress in solving the problems especially as they relate to health and disease. This suggests that close collaboration between chemists and biologists is not only necessary but essential for progress in both the biology and chemistry that will provide solutions to the global questions of biology. This perspective has directed my scientific efforts for the past 45 years, and in this overview I provide my perspective of how the applications of synthetic chemistry, structural design, and numerous other chemical principles have intersected in my collaborations with biologists to provide new tools, new science, and new insights that were only made possible and fruitful by these collaborations.

  5. Using Biocatalysis to Integrate Organic Chemistry into a Molecular Biology Laboratory Course

    Science.gov (United States)

    Beers, Mande; Archer, Crystal; Feske, Brent D.; Mateer, Scott C.

    2012-01-01

    Current cutting-edge biomedical investigation requires that the researcher have an operational understanding of several diverse disciplines. Biocatalysis is a field of science that operates at the crossroads of organic chemistry, biochemistry, microbiology, and molecular biology, and provides an excellent model for interdisciplinary research. We…

  6. Connecting biology and organic chemistry introductory laboratory courses through a collaborative research project.

    Science.gov (United States)

    Boltax, Ariana L; Armanious, Stephanie; Kosinski-Collins, Melissa S; Pontrello, Jason K

    2015-01-01

    Modern research often requires collaboration of experts in fields, such as math, chemistry, biology, physics, and computer science to develop unique solutions to common problems. Traditional introductory undergraduate laboratory curricula in the sciences often do not emphasize connections possible between the various disciplines. We designed an interdisciplinary, medically relevant, project intended to help students see connections between chemistry and biology. Second term organic chemistry laboratory students designed and synthesized potential polymer inhibitors or inducers of polyglutamine protein aggregation. The use of novel target compounds added the uncertainty of scientific research to the project. Biology laboratory students then tested the novel potential pharmaceuticals in Huntington's disease model assays, using in vitro polyglutamine peptide aggregation and in vivo lethality studies in Drosophila. Students read articles from the primary literature describing the system from both chemical and biological perspectives. Assessment revealed that students emerged from both courses with a deeper understanding of the interdisciplinary nature of biology and chemistry and a heightened interest in basic research. The design of this collaborative project for introductory biology and organic chemistry labs demonstrated how the local interests and expertise at a university can be drawn from to create an effective way to integrate these introductory courses. Rather than simply presenting a series of experiments to be replicated, we hope that our efforts will inspire other scientists to think about how some aspect of authentic work can be brought into their own courses, and we also welcome additional collaborations to extend the scope of the scientific exploration. © 2015 The International Union of Biochemistry and Molecular Biology.

  7. Digital biology and chemistry.

    Science.gov (United States)

    Witters, Daan; Sun, Bing; Begolo, Stefano; Rodriguez-Manzano, Jesus; Robles, Whitney; Ismagilov, Rustem F

    2014-09-07

    This account examines developments in "digital" biology and chemistry within the context of microfluidics, from a personal perspective. Using microfluidics as a frame of reference, we identify two areas of research within digital biology and chemistry that are of special interest: (i) the study of systems that switch between discrete states in response to changes in chemical concentration of signals, and (ii) the study of single biological entities such as molecules or cells. In particular, microfluidics accelerates analysis of switching systems (i.e., those that exhibit a sharp change in output over a narrow range of input) by enabling monitoring of multiple reactions in parallel over a range of concentrations of signals. Conversely, such switching systems can be used to create new kinds of microfluidic detection systems that provide "analog-to-digital" signal conversion and logic. Microfluidic compartmentalization technologies for studying and isolating single entities can be used to reconstruct and understand cellular processes, study interactions between single biological entities, and examine the intrinsic heterogeneity of populations of molecules, cells, or organisms. Furthermore, compartmentalization of single cells or molecules in "digital" microfluidic experiments can induce switching in a range of reaction systems to enable sensitive detection of cells or biomolecules, such as with digital ELISA or digital PCR. This "digitizing" offers advantages in terms of robustness, assay design, and simplicity because quantitative information can be obtained with qualitative measurements. While digital formats have been shown to improve the robustness of existing chemistries, we anticipate that in the future they will enable new chemistries to be used for quantitative measurements, and that digital biology and chemistry will continue to provide further opportunities for measuring biomolecules, understanding natural systems more deeply, and advancing molecular and

  8. Bridging the gap between cell biology and organic chemistry: chemical synthesis and biological application of lipidated peptides and proteins.

    Science.gov (United States)

    Peters, Carsten; Wagner, Melanie; Völkert, Martin; Waldmann, Herbert

    2002-09-01

    We have developed a basic concept for studying cell biological phenomena using an interdisciplinary approach starting from organic chemistry. Based on structural information available for a given biological phenomenon, unsolved chemical problems are identified. For their solution, new synthetic pathways and methods are developed, which reflect the state of the art in synthesising lipidated peptide conjugates. These compounds are used as molecular probes for the investigation of biological phenomena that involve both the determination of biophysical properties and cell biological studies. The interplay between organic synthesis, biophysics and cell biology in the study of protein lipidation may open up new and alternative opportunities to gain knowledge about the biological phenomenon that could not be obtained by employing biological techniques alone. This fruitful combination is highlighted using the Ras protein as an outstanding example. Included herein is: the development of methods for the synthesis of Ras-derived peptides and fully functional Ras proteins, the determination of the biophysical properties, in particular the ability to bind to model membranes, and finally the use of synthetic Ras peptides and proteins in cell biological experiments.

  9. Design, Development, and Psychometric Analysis of a General, Organic, and Biological Chemistry Topic Inventory Based on the Identified Main Chemistry Topics Relevant to Nursing Clinical Practice

    Science.gov (United States)

    Brown, Corina E.

    2013-01-01

    This two-stage study focused on the undergraduate nursing course that covers topics in general, organic, and biological (GOB) chemistry. In the first stage, the central objective was to identify the main concepts of GOB chemistry relevant to the clinical practice of nursing. The collection of data was based on open-ended interviews of both nursing…

  10. Two Methods of Determining Total Phenolic Content of Foods and Juices in a General, Organic, and Biological (GOB) Chemistry Lab

    Science.gov (United States)

    Shaver, Lee Alan; Leung, Sam H.; Puderbaugh, Amy; Angel, Stephen A.

    2011-01-01

    The determination of total phenolics in foods and fruit juices was used successfully as a laboratory experiment in our undergraduate general, organic, and biological (GOB) chemistry course. Two different colorimetric methods were used over three years and comparative student results indicate that a ferrous ammonium sulfate (FAS) indicator…

  11. Connecting Biology and Organic Chemistry Introductory Laboratory Courses through a Collaborative Research Project

    Science.gov (United States)

    Boltax, Ariana L.; Armanious, Stephanie; Kosinski-Collins, Melissa S.; Pontrello, Jason K.

    2015-01-01

    Modern research often requires collaboration of experts in fields, such as math, chemistry, biology, physics, and computer science to develop unique solutions to common problems. Traditional introductory undergraduate laboratory curricula in the sciences often do not emphasize connections possible between the various disciplines. We designed an…

  12. Theoretical chemistry periodicities in chemistry and biology

    CERN Document Server

    Eyring, Henry

    1978-01-01

    Theoretical Chemistry: Periodicities in Chemistry and Biology, Volume 4 covers the aspects of theoretical chemistry. The book discusses the stably rotating patterns of reaction and diffusion; the chemistry of inorganic systems exhibiting nonmonotonic behavior; and population cycles. The text also describes the mathematical modeling of excitable media in neurobiology and chemistry; oscillating enzyme reactions; and oscillatory properties and excitability of the heart cell membrane. Selected topics from the theory of physico-chemical instabilities are also encompassed. Chemists, mechanical engin

  13. Medicinal Chemistry/Pharmacology in Sophomore Organic Chemistry.

    Science.gov (United States)

    Harrison, Aline M.

    1989-01-01

    Discussed is a series of lectures designed to illustrate the use of general organic chemical principles in molecular biology, introduce current research in interdisciplinary areas to the beginner, increase interest in organic chemistry, and bridge the gap between traditional organic chemistry, biology, and the consumer. An outline is presented.…

  14. Organic chemistry experiment

    International Nuclear Information System (INIS)

    Mun, Seok Sik

    2005-02-01

    This book deals with organic chemistry experiments, it is divided five chapters, which have introduction, the way to write the experiment report and safety in the laboratory, basic experiment technic like recrystallization and extraction, a lot of organic chemistry experiments such as fischer esterification, ester hydrolysis, electrophilic aromatic substitution, aldol reaction, benzoin condensation, wittig reaction grignard reaction, epoxidation reaction and selective reduction. The last chapter introduces chemistry site on the internet and way to find out reference on chemistry.

  15. Some aspects of the organic, biological and inorganic chemistry of astatine

    International Nuclear Information System (INIS)

    Visser, G.W.M.

    1982-01-01

    Astatine has no stable isotopes and the radioactive isotopes with half-lives sufficiently long for chemical experiments ( 209 At, 210 At, 211 At) must be produced artificially with a cyclotron or with a high energy accelerator by spallation of Th. This thesis deals with the synthesis and chemistry of At-compounds and the determination of some of their properties. (C.F.)

  16. Current organic chemistry

    National Research Council Canada - National Science Library

    1997-01-01

    Provides in depth reviews on current progress in the fields of asymmetric synthesis, organometallic chemistry, bioorganic chemistry, heterocyclic chemistry, natural product chemistry, and analytical...

  17. Organic Chemistry in Space

    Science.gov (United States)

    Charnley, Steven

    2009-01-01

    Astronomical observations, theoretical modeling, laboratory simulation and analysis of extraterrestrial material have enhanced our knowledge of the inventory of organic matter in the interstellar medium (ISM) and on small bodies such as comets and asteroids (Ehrenfreund & Charnley 2000). Comets, asteroids and their fragments, meteorites and interplanetary dust particles (IDPs), contributed significant amounts of extraterrestrial organic matter to the young Earth. This material degraded and reacted in a terrestrial prebiotic chemistry to form organic structures that may have served as building blocks for life on the early Earth. In this talk I will summarize our current understanding of the organic composition and chemistry of interstellar clouds. Molecules of astrobiological relevance include the building blocks of our genetic material: nucleic acids, composed of subunits such as N-heterocycles (purines and pyrimidines), sugars and amino acids. Signatures indicative of inheritance of pristine and modified interstellar material in comets and meteorites will also be discussed.

  18. Chemistry and biology by new multiple choice

    International Nuclear Information System (INIS)

    Seo, Hyeong Seok; Kim, Seong Hwan

    2003-02-01

    This book is divided into two parts, the first part is about chemistry, which deals with science of material, atom structure and periodic law, chemical combination and power between molecule, state of material and solution, chemical reaction and an organic compound. The second part give description of biology with molecule and cell, energy in cells and chemical synthesis, molecular biology and heredity, function on animal, function on plant and evolution and ecology. This book has explanation of chemistry and biology with new multiple choice.

  19. Natural Proline-Rich Cyclopolypeptides from Marine Organisms: Chemistry, Synthetic Methodologies and Biological Status.

    Science.gov (United States)

    Fang, Wan-Yin; Dahiya, Rajiv; Qin, Hua-Li; Mourya, Rita; Maharaj, Sandeep

    2016-10-26

    Peptides have gained increased interest as therapeutics during recent years. More than 60 peptide drugs have reached the market for the benefit of patients and several hundreds of novel therapeutic peptides are in preclinical and clinical development. The key contributor to this success is the potent and specific, yet safe, mode of action of peptides. Among the wide range of biologically-active peptides, naturally-occurring marine-derived cyclopolypeptides exhibit a broad range of unusual and potent pharmacological activities. Because of their size and complexity, proline-rich cyclic peptides (PRCPs) occupy a crucial chemical space in drug discovery that may provide useful scaffolds for modulating more challenging biological targets, such as protein-protein interactions and allosteric binding sites. Diverse pharmacological activities of natural cyclic peptides from marine sponges, tunicates and cyanobacteria have encouraged efforts to develop cyclic peptides with well-known synthetic methods, including solid-phase and solution-phase techniques of peptide synthesis. The present review highlights the natural resources, unique structural features and the most relevant biological properties of proline-rich peptides of marine-origin, focusing on the potential therapeutic role that the PRCPs may play as a promising source of new peptide-based novel drugs.

  20. Interstellar organic chemistry.

    Science.gov (United States)

    Sagan, C.

    1972-01-01

    Most of the interstellar organic molecules have been found in the large radio source Sagittarius B2 toward the galactic center, and in such regions as W51 and the IR source in the Orion nebula. Questions of the reliability of molecular identifications are discussed together with aspects of organic synthesis in condensing clouds, degradational origin, synthesis on grains, UV natural selection, interstellar biology, and contributions to planetary biology.

  1. XVIII Mendeleev congress on general and applied chemistry. Summaries of reports in five volumes. Volume 5. IV Russian-French symposium Supramolecular systems in chemistry and biology. II Russian-Indian symposium on organic chemistry. International symposium on present-day radiochemistry Radiochemistry: progress and prospects. International symposium Green chemistry, stable evolution and social responsibility of chemists. Symposium Nucleophilic hydrogen substitution in aromatic systems and related reactions

    International Nuclear Information System (INIS)

    2007-01-01

    The 5 volume of the XVIII Mendeleev congress on general and applied chemistry includes summaries of reports on the subjects of sypramolecular systems in chemistry and biology, organic chemistry, modern radiochemistry, green chemistry - development and social responsibility of chemists, nucleophilic hydrogen substitution in aromatic systems and related chemical reactions [ru

  2. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 7. Learning Organic Chemistry Through Natural engine Products - Structure and Biological Functions. N R Krishnaswamy. Series Article Volume 1 Issue 7 July 1996 pp 23-30 ...

  3. Combining supramolecular chemistry with biology.

    Science.gov (United States)

    Uhlenheuer, Dana A; Petkau, Katja; Brunsveld, Luc

    2010-08-01

    Supramolecular chemistry has primarily found its inspiration in biological molecules, such as proteins and lipids, and their interactions. Currently the supramolecular assembly of designed compounds can be controlled to great extent. This provides the opportunity to combine these synthetic supramolecular elements with biomolecules for the study of biological phenomena. This tutorial review focuses on the possibilities of the marriage of synthetic supramolecular architectures and biological systems. It highlights that synthetic supramolecular elements are for example ideal platforms for the recognition and modulation of proteins and cells. The unique features of synthetic supramolecular systems with control over size, shape, valency, and interaction strength allow the generation of structures fitting the demands to approach the biological problems at hand. Supramolecular chemistry has come full circle, studying the biology and its molecules which initially inspired its conception.

  4. The C–F bond as a conformational tool in organic and biological chemistry

    Directory of Open Access Journals (Sweden)

    Luke Hunter

    2010-04-01

    Full Text Available Organofluorine compounds are widely used in many different applications, ranging from pharmaceuticals and agrochemicals to advanced materials and polymers. It has been recognised for many years that fluorine substitution can confer useful molecular properties such as enhanced stability and hydrophobicity. Another impact of fluorine substitution is to influence the conformations of organic molecules. The stereoselective introduction of fluorine atoms can therefore be exploited as a conformational tool for the synthesis of shape-controlled functional molecules. This review will begin by describing some general aspects of the C–F bond and the various conformational effects associated with C–F bonds (i.e. dipole–dipole interactions, charge–dipole interactions and hyperconjugation. Examples of functional molecules that exploit these conformational effects will then be presented, drawing from a diverse range of molecules including pharmaceuticals, organocatalysts, liquid crystals and peptides.

  5. Organic chemistry on Titan

    Science.gov (United States)

    Chang, S.; Scattergood, T.; Aronowitz, S.; Flores, J.

    1979-01-01

    Features taken from various models of Titan's atmosphere are combined in a working composite model that provides environmental constraints within which different pathways for organic chemical synthesis are determined. Experimental results and theoretical modeling suggest that the organic chemistry of the satellite is dominated by two processes: photochemistry and energetic particle bombardment. Photochemical reactions of CH4 in the upper atmosphere can account for the presence of C2 hydrocarbons. Reactions initiated at various levels of the atmosphere by cosmic rays, Saturn 'wind', and solar wind particle bombardment of a CH4-N2 atmospheric mixture can account for the UV-visible absorbing stratospheric haze, the reddish appearance of the satellite, and some of the C2 hydrocarbons. In the lower atmosphere photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. It is concluded that the surface of Titan may contain ancient or recent organic matter (or both) produced in the atmosphere.

  6. Plastic Organic Scintillator Chemistry

    Science.gov (United States)

    Brightwell, C. R.; Temanson, E. S.; Febbraro, M. T.

    2017-09-01

    Due to their high light output, quick decay time, affordability, durability and ability to be molded, plastic organic scintillators are increasingly becoming a more viable method of particle detection. Since the plastic is composed entirely of single molecular chains with repeating units, scintillating properties remain stable despite changes in experimental conditions. Different scintillating plastics can be modified and tailored to suit specific experiments depending on a variety of requirements such as light output, scintillating wavelength, and PMT compatibility. The synthesis chemistry of a recent but well-known scintillating polyester, polyethylene naphthalate (PEN) will be presented to demonstrate how plastic organic scintillators can be modified for different particle detection experiments. PEN has been successfully synthesized at ORNL, and procedures are currently being investigated to modify PEN using different reactants and catalysts. The goal is to achieve a transparent scintillating plastic with an incorporated wavelength shifter in the chain that scintillates with a wavelength around 440 nm. The status of this project will be presented. This research is supported by the U. S. Department of Energy Office of Science.

  7. Exploration of fluorine chemistry at the multidisciplinary interface of chemistry and biology.

    Science.gov (United States)

    Ojima, Iwao

    2013-07-05

    Over the last three decades, my engagement in "fluorine chemistry" has evolved substantially because of the multidisciplinary nature of the research programs. I began my research career as a synthetic chemist in organometallic chemistry and homogeneous catalysis directed toward organic synthesis. Then, I was brought into a very unique world of "fluorine chemistry" in the end of 1970s. I started exploring the interface of fluorine chemistry and transition metal homogeneous catalysis first, which was followed by amino acids, peptides, and peptidomimetics for medicinal chemistry. Since then, I have been exploring the interfaces of fluorine chemistry and multidisciplinary fields of research involving medicinal chemistry, chemical biology, cancer biology, and molecular imaging. This perspective intends to cover my fruitful endeavor in the exploration of fluorine chemistry at the multidisciplinary interface of chemistry and biology in a chronological order to show the evolution of my research interest and strategy.

  8. Allicin: Chemistry and Biological Properties

    Directory of Open Access Journals (Sweden)

    Jan Borlinghaus

    2014-08-01

    Full Text Available Allicin (diallylthiosulfinate is a defence molecule from garlic (Allium sativum L. with a broad range of biological activities. Allicin is produced upon tissue damage from the non-proteinogenic amino acid alliin (S-allylcysteine sulfoxide in a reaction that is catalyzed by the enzyme alliinase. Current understanding of the allicin biosynthetic pathway will be presented in this review. Being a thiosulfinate, allicin is a reactive sulfur species (RSS and undergoes a redox-reaction with thiol groups in glutathione and proteins that is thought to be essential for its biological activity. Allicin is physiologically active in microbial, plant and mammalian cells. In a dose-dependent manner allicin can inhibit the proliferation of both bacteria and fungi or kill cells outright, including antibiotic-resistant strains like methicillin-resistant Staphylococcus aureus (MRSA. Furthermore, in mammalian cell lines, including cancer cells, allicin induces cell-death and inhibits cell proliferation. In plants allicin inhibits seed germination and attenuates root-development. The majority of allicin’s effects are believed to be mediated via redox-dependent mechanisms. In sub-lethal concentrations, allicin has a variety of health-promoting properties, for example cholesterol- and blood pressure-lowering effects that are advantageous for the cardio-vascular system. Clearly, allicin has wide-ranging and interesting applications in medicine and (green agriculture, hence the detailed discussion of its enormous potential in this review. Taken together, allicin is a fascinating biologically active compound whose properties are a direct consequence of the molecule’s chemistry.

  9. Emerging trends at the interface of Chemistry and Biology ...

    Indian Academy of Sciences (India)

    Emerging trends at the interface of Chemistry and. Biology: Applications to the design of human therapeutics. SANTANU BHATTACHARYA. 1 and RAGHAVAN VARADARAJAN. 2. 1. Department of Organic Chemistry, Indian Institute of Science, Bangalore 560 012, India. e-mail: sb@orgchem.iisc.ernet.in. 2. Molecular ...

  10. Mass spectrometry. [in organic chemistry

    Science.gov (United States)

    Burlingame, A. L.; Shackleton, C. H. L.; Howe, I.; Chizhov, O. S.

    1978-01-01

    A review of mass spectrometry in organic chemistry is given, dealing with advances in instrumentation and computer techniques, selected topics in gas-phase ion chemistry, and applications in such fields as biomedicine, natural-product studies, and environmental pollution analysis. Innovative techniques and instrumentation are discussed, along with chromatographic-mass spectrometric on-line computer techniques, mass spectral interpretation and management techniques, and such topics in gas-phase ion chemistry as electron-impact ionization and decomposition, photoionization, field ionization and desorption, high-pressure mass spectrometry, ion cyclotron resonance, and isomerization reactions of organic ions. Applications of mass spectrometry are examined with respect to bio-oligomers and their constituents, biomedically important substances, microbiology, environmental organic analysis, and organic geochemistry.

  11. Titan's organic chemistry

    Science.gov (United States)

    Sagan, C.; Thompson, W. R.; Khare, B. N.

    1985-01-01

    Voyager discovered nine simple organic molecules in the atmosphere of Titan. Complex organic solids, called tholins, produced by irradiation of the simulated Titanian atmosphere, are consistent with measured properties of Titan from ultraviolet to microwave frequencies and are the likely main constituents of the observed red aerosols. The tholins contain many of the organic building blocks central to life on earth. At least 100-m, and possibly kms thicknesses of complex organics have been produced on Titan during the age of the solar system, and may exist today as submarine deposits beneath an extensive ocean of simple hydrocarbons.

  12. The biological inorganic chemistry of zinc ions.

    Science.gov (United States)

    Krężel, Artur; Maret, Wolfgang

    2016-12-01

    The solution and complexation chemistry of zinc ions is the basis for zinc biology. In living organisms, zinc is redox-inert and has only one valence state: Zn(II). Its coordination environment in proteins is limited by oxygen, nitrogen, and sulfur donors from the side chains of a few amino acids. In an estimated 10% of all human proteins, zinc has a catalytic or structural function and remains bound during the lifetime of the protein. However, in other proteins zinc ions bind reversibly with dissociation and association rates commensurate with the requirements in regulation, transport, transfer, sensing, signalling, and storage. In contrast to the extensive knowledge about zinc proteins, the coordination chemistry of the "mobile" zinc ions in these processes, i.e. when not bound to proteins, is virtually unexplored and the mechanisms of ligand exchange are poorly understood. Knowledge of the biological inorganic chemistry of zinc ions is essential for understanding its cellular biology and for designing complexes that deliver zinc to proteins and chelating agents that remove zinc from proteins, for detecting zinc ion species by qualitative and quantitative analysis, and for proper planning and execution of experiments involving zinc ions and nanoparticles such as zinc oxide (ZnO). In most investigations, reference is made to zinc or Zn 2+ without full appreciation of how biological zinc ions are buffered and how the d-block cation Zn 2+ differs from s-block cations such as Ca 2+ with regard to significantly higher affinity for ligands, preference for the donor atoms of ligands, and coordination dynamics. Zinc needs to be tightly controlled. The interaction with low molecular weight ligands such as water and inorganic and organic anions is highly relevant to its biology but in contrast to its coordination in proteins has not been discussed in the biochemical literature. From the discussion in this article, it is becoming evident that zinc ion speciation is

  13. Organic Chemistry of Meteorites

    Science.gov (United States)

    Chang, S.; Morrison, David (Technical Monitor)

    1994-01-01

    Studies of the molecular structures and C,N,H-isotopic compositions of organic matter in meteorites reveal a complex history beginning in the parent interstellar cloud which spawned the solar system. Incorporation of interstellar dust and gas in the protosolar nebula followed by further thermal and aqueous processing on primordial parent bodies of carbonaceous, meteorites have produced an inventory of diverse organic compounds including classes now utilized in biochemistry. This inventory represents one possible set of reactants for chemical models for the origin of living systems on the early Earth. Evidence bearing on the history of meteoritic organic matter from astronomical observations and laboratory investigations will be reviewed and future research directions discussed.

  14. Molecular biology: Self-sustaining chemistry

    Directory of Open Access Journals (Sweden)

    Wrede Paul

    2007-10-01

    Full Text Available Abstract Molecular biology is an established interdisciplinary field within biology that deals fundamentally with the function of any nucleic acid in the cellular context. The molecular biology section in Chemistry Central Journal focusses on the genetically determined chemistry and biochemistry occuring in the cell. How can thousands of chemical reactions interact smoothly to maintain the life of cells, even in a variable environment? How is this self-sustaining system achieved? These are questions that should be answered in the light of molecular biology and evolution, but with the application of biophysical, physico-chemical, analytical and preparative technologies. As the Section Editor for the molecular biology section in Chemistry Central Journal, I hope to receive manuscripts that present new approaches aimed at better answering and shedding light upon these fascinating questions related to the chemistry of livings cells.

  15. Radiation chemistry comes before radiation biology.

    Science.gov (United States)

    O'Neill, Peter; Wardman, Peter

    2009-01-01

    This article seeks to illustrate some contributions of radiation chemistry to radiobiology and related science, and to draw attention to examples where radiation chemistry is central to our knowledge of specific aspects. Radiation chemistry is a mature branch of radiation science which is continually evolving and finding wider applications. This is particularly apparent in the study of the roles of free radicals in biology generally, and radiation biology specifically. The chemical viewpoint helps unite the spatial and temporal insight coming from radiation physics with the diversity of biological responses. While historically, the main application of radiation chemistry of relevance to radiation biology has been investigations of the free-radical processes leading to radiation-induced DNA damage and its chemical characterization, two features of radiation chemistry point to its wider importance. First, its emphasis on quantification and characterization at the molecular level helps provide links between DNA damage, biochemical repair processes, and mutagenicity and radiosensitivity. Second, its central pillar of chemical kinetics aids understanding of the roles of 'reactive oxygen species' in cell signalling and diverse biological effects more generally, and application of radiation chemistry in the development of drugs to enhance radiotherapy and as hypoxia-specific cytotoxins or diagnostic agents. The illustrations of the broader applications of radiation chemistry in this article focus on their relevance to radiation biology and demonstrate the importance of synergy in the radiation sciences. The past contributions of radiation chemistry to radiation biology are evident, but there remains considerable potential to help advance future biological understanding using the knowledge and techniques of radiation chemistry.

  16. Organic Chemistry Trivia: A Way to Interest Nonchemistry Majors

    Science.gov (United States)

    Farmer, Steven C.

    2011-01-01

    The use of in-class stories is an excellent way to keep a class interested in subject matter. Many organic chemistry classes are populated by nonchemistry majors, such as pre-med, pre-pharm, and biology students. Trivia questions are presented that are designed to show how organic chemistry is an important subject to students regardless of their…

  17. Are Biology and Chemistry Out of Order?

    Science.gov (United States)

    Gaudin, Felix A.

    1984-01-01

    Discusses advantages and disadvantages of standard high school biology and chemistry course sequences. Relates these sequences to Piagetian developmental levels as well as to David Ausubel's cognitive theory. Suggests that the sequences be reexamined in light of issues considered. (JM)

  18. Photoredox Catalysis in Organic Chemistry

    Science.gov (United States)

    2016-01-01

    In recent years, photoredox catalysis has come to the forefront in organic chemistry as a powerful strategy for the activation of small molecules. In a general sense, these approaches rely on the ability of metal complexes and organic dyes to convert visible light into chemical energy by engaging in single-electron transfer with organic substrates, thereby generating reactive intermediates. In this Perspective, we highlight the unique ability of photoredox catalysis to expedite the development of completely new reaction mechanisms, with particular emphasis placed on multicatalytic strategies that enable the construction of challenging carbon–carbon and carbon–heteroatom bonds. PMID:27477076

  19. Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

    Science.gov (United States)

    Bradfield, A.D.; Flexner, N.M.; Webster, D.A.

    1993-01-01

    An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated

  20. Cell-free biology: exploiting the interface between synthetic biology and synthetic chemistry.

    Science.gov (United States)

    Harris, D Calvin; Jewett, Michael C

    2012-10-01

    Just as synthetic organic chemistry once revolutionized the ability of chemists to build molecules (including those that did not exist in nature) following a basic set of design rules, cell-free synthetic biology is beginning to provide an improved toolbox and faster process for not only harnessing but also expanding the chemistry of life. At the interface between chemistry and biology, research in cell-free synthetic systems is proceeding in two different directions: using synthetic biology for synthetic chemistry and using synthetic chemistry to reprogram or mimic biology. In the coming years, the impact of advances inspired by these approaches will make possible the synthesis of nonbiological polymers having new backbone compositions, new chemical properties, new structures, and new functions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Recent advances in the chemistry and biology of pyridopyrimidines.

    Science.gov (United States)

    Buron, F; Mérour, J Y; Akssira, M; Guillaumet, G; Routier, S

    2015-05-05

    The interest in pyridopyrimidine cores for pharmaceutical products makes this scaffold a highly useful building block for organic chemistry. These derivatives have found applications in various areas of medicine such as anticancer, CNS, fungicidal, antiviral, anti-inflammatory, antimicrobial, and antibacterial therapies. This review mainly focuses on the progress achieved since 2004 in the chemistry and biological activity of pyridopyrimidines. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  2. Organic Chemistry Self Instructional Package 2: Methane.

    Science.gov (United States)

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  3. Reaction-Map of Organic Chemistry

    Science.gov (United States)

    Murov, Steven

    2007-01-01

    The Reaction-Map of Organic Chemistry lists all the most commonly studied reactions in organic chemistry on one page. The discussed Reaction-Map will act as another learning aide for the students, making the study of organic chemistry much easier.

  4. From coordination chemistry to biological chemistry of aluminium.

    Science.gov (United States)

    Kiss, Tamas

    2013-11-01

    The paper gives a review on the importance of distribution of Al in biological fluids, primarily in the lights of the works of the author in Al chemistry. It starts with studies of interactions of Al(III) with small biomolecules, such as aliphatic and aromatic hydroxycarboxylic acids, and inorganic and organic phosphates. A significant part of this review deals with the problems of description of the biospeciation of Al(III) in serum, where besides the thermodynamic conditions the role of time is also considered in the case of this sluggish metal ion. The Al(III) complexes of the other large group of biomolecules, proteins and their building blocks (oligo)peptides and amino acids are also discussed, where the role of the type of the side chain donors and the extent of preorganisation are considered in the efficiency of metal ion binding. The application of low molecular mass chelator molecules in restoring the dysfunctioning metal ion (including Al(III)) homeostasis in the treatment of Alzheimer's disease is also discussed in the paper. © 2013.

  5. Cellular uptake: lessons from supramolecular organic chemistry.

    Science.gov (United States)

    Gasparini, Giulio; Bang, Eun-Kyoung; Montenegro, Javier; Matile, Stefan

    2015-07-04

    The objective of this Feature Article is to reflect on the importance of established and emerging principles of supramolecular organic chemistry to address one of the most persistent problems in life sciences. The main topic is dynamic covalent chemistry on cell surfaces, particularly disulfide exchange for thiol-mediated uptake. Examples of boronate and hydrazone exchange are added for contrast, comparison and completion. Of equal importance are the discussions of proximity effects in polyions and counterion hopping, and more recent highlights on ring tension and ion pair-π interactions. These lessons from supramolecular organic chemistry apply to cell-penetrating peptides, particularly the origin of "arginine magic" and the "pyrenebutyrate trick," and the currently emerging complementary "disulfide magic" with cell-penetrating poly(disulfide)s. They further extend to the voltage gating of neuronal potassium channels, gene transfection, and the delivery of siRNA. The collected examples illustrate that the input from conceptually innovative chemistry is essential to address the true challenges in biology beyond incremental progress and random screening.

  6. Organic chemistry of elemental phosphorus

    International Nuclear Information System (INIS)

    Milyukov, V A; Budnikova, Yulia H; Sinyashin, Oleg G

    2005-01-01

    The principal achievements and the modern trends in the development of the chemistry of elemental phosphorus are analysed, described systematically and generalised. The possibilities and advantages of the preparation of organophosphorus compounds directly from white phosphorus are demonstrated. Attention is focused on the activation and transformation of elemental phosphorus in the coordination sphere of transition metal complexes. The mechanisms of the reactions of white phosphorus with nucleophilic and electrophilic reagents are discussed. Electrochemical approaches to the synthesis of organic phosphorus derivatives based on white phosphorus are considered.

  7. Chemistry of Covalent Organic Frameworks.

    Science.gov (United States)

    Waller, Peter J; Gándara, Felipe; Yaghi, Omar M

    2015-12-15

    growing library of linkers amenable to the synthesis of COFs is now available, and new COFs and topologies made by reticular synthesis are being reported. Much research is also directed toward the development of new methods of linking organic building units to generate other crystalline COFs. These efforts promise not only new COF chemistry and materials, but also the chance to extend the precision of molecular covalent chemistry to extended solids.

  8. Microwaves in organic chemistry and organic chemical

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2005-01-01

    Full Text Available The usual way of applying heat to a chemical reaction is the use of a Bunsen burner, an oil or some other type of bath, or an electric heater. In inorganic chemistry, microwave technology has been used since the late 1970s while it has been implemented in organic chemistry since the mid-1980s. Microwave heating has been used in the food industry for almost fifty years. The shorter reaction times and expanded reaction range that is offered by microwave technology are suited to the increased demands in industry. For example, there is a requirement in the pharmaceutical industry for a higher number of a novel chemical entities to be produced, which requires chemists to employ a number of resources to reduce time for the production of compounds. Also, microwaves are used in the food industry, as well as in the pyrolysis of waste materials, sample preparation, the solvent extraction of natural products and the hydrolysis of proteins and peptides.

  9. Incorporation of Medicinal Chemistry into the Organic Chemistry Curriculum

    Science.gov (United States)

    Forbes, David C.

    2004-01-01

    Application of concepts presented in organic chemistry lecture using a virtual project involving the sythesis of medicinally important compounds is emphasized. The importance of reinforcing the concepts from lecture in lab, thus providing a powerful instructional means is discussed.

  10. Biological nitric oxide signalling: chemistry and terminology

    Science.gov (United States)

    Heinrich, Tassiele A; da Silva, Roberto S; Miranda, Katrina M; Switzer, Christopher H; Wink, David A; Fukuto, Jon M

    2013-01-01

    Biological nitrogen oxide signalling and stress is an area of extreme clinical, pharmacological, toxicological, biochemical and chemical research interest. The utility of nitric oxide and derived species as signalling agents is due to their novel and vast chemical interactions with a variety of biological targets. Herein, the chemistry associated with the interaction of the biologically relevant nitrogen oxide species with fundamental biochemical targets is discussed. Specifically, the chemical interactions of nitrogen oxides with nucleophiles (e.g. thiols), metals (e.g. hemeproteins) and paramagnetic species (e.g. dioxygen and superoxide) are addressed. Importantly, the terms associated with the mechanisms by which NO (and derived species) react with their respective biological targets have been defined by numerous past chemical studies. Thus, in order to assist researchers in referring to chemical processes associated with nitrogen oxide biology, the vernacular associated with these chemical interactions is addressed. PMID:23617570

  11. Statistical Automatic Summarization in Organic Chemistry

    OpenAIRE

    Boudin, Florian; Velazquez-Morales, Patricia; Torres-Moreno, Juan-Manuel

    2009-01-01

    We present an oriented numerical summarizer algorithm, applied to producing automatic summaries of scientific documents in Organic Chemistry. We present its implementation named Yachs (Yet Another Chemistry Summarizer) that combines a specific document pre-processing with a sentence scoring method relying on the statistical properties of documents. We show that Yachs achieves the best results among several other summarizers on a corpus of Organic Chemistry articles.

  12. Mendeleev-2013. VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials. Book of abstracts. Section 4. Organic chemistry

    International Nuclear Information System (INIS)

    2013-01-01

    VII All-Russian conference of young scientists, postgraduate students and students with international participation on chemistry and nanomaterials was conducted on the Chemistry department of Saint-Petersburg University on April, 2-5, 2013. In the conference participants from 14 countries took part. There were five sections: Nanochemistry and nanomaterials, Analytic chemistry, Inorganic chemistry, Organic chemistry, Physical chemistry. In the collection (Section 2 - Organic chemistry) there are the abstracts concerning different aspects of organic chemistry: synthesis and study of properties of heterocyclic, organometallic, biologically active, medicinal compounds, new ion exchange materials, reagents for analytic chemistry, etc [ru

  13. Undergraduate Organic Chemistry Laboratory Safety

    Science.gov (United States)

    Luckenbaugh, Raymond W.

    1996-11-01

    Each organic chemistry student should become familiar with the educational and governmental laboratory safety requirements. One method for teaching laboratory safety is to assign each student to locate safety resources for a specific class laboratory experiment. The student should obtain toxicity and hazardous information for all chemicals used or produced during the assigned experiment. For example, what is the LD50 or LC50 for each chemical? Are there any specific hazards for these chemicals, carcinogen, mutagen, teratogen, neurotixin, chronic toxin, corrosive, flammable, or explosive agent? The school's "Chemical Hygiene Plan", "Prudent Practices for Handling Hazardous Chemicals in the Laboratory" (National Academy Press), and "Laboratory Standards, Part 1910 - Occupational Safety and Health Standards" (Fed. Register 1/31/90, 55, 3227-3335) should be reviewed for laboratory safety requirements for the assigned experiment. For example, what are the procedures for safe handling of vacuum systems, if a vacuum distillation is used in the assigned experiment? The literature survey must be submitted to the laboratory instructor one week prior to the laboratory session for review and approval. The student should then give a short presentation to the class on the chemicals' toxicity and hazards and describe the safety precautions that must be followed. This procedure gives the student first-hand knowledge on how to find and evaluate information to meet laboartory safety requirements.

  14. Green chemistry oriented organic synthesis in water.

    Science.gov (United States)

    Simon, Marc-Olivier; Li, Chao-Jun

    2012-02-21

    The use of water as solvent features many benefits such as improving reactivities and selectivities, simplifying the workup procedures, enabling the recycling of the catalyst and allowing mild reaction conditions and protecting-group free synthesis in addition to being benign itself. In addition, exploring organic chemistry in water can lead to uncommon reactivities and selectivities complementing the organic chemists' synthetic toolbox in organic solvents. Studying chemistry in water also allows insight to be gained into Nature's way of chemical synthesis. However, using water as solvent is not always green. This tutorial review briefly discusses organic synthesis in water with a Green Chemistry perspective.

  15. Novel Aryne Chemistry in Organic Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhijian [Iowa State Univ., Ames, IA (United States)

    2006-12-12

    Arynes are among the most intensively studied systems in chemistry. However, many aspects of the chemistry of these reactive intermediates are not well understood yet and their use as reagents in synthetic organic chemistry has been somewhat limited, due to the harsh conditions needed to generate arynes and the often uncontrolled reactivity exhibited by these species. Recently, o-silylaryl triflates, which can generate the corresponding arynes under very mild reaction conditions, have been found very useful in organic synthesis. This thesis describes several novel and useful methodologies by employing arynes, which generate from o-silylaryl triflates, in organic synthesis. An efficient, reliable method for the N-arylation of amines, sulfonamides and carbamates, and the O-arylation of phenols and carboxylic acids is described in Chapter 1. Amines, sulfonamides, phenols, and carboxylic acids are good nucleophiles, which can react with arynes generated from a-silylaryl triflates to afford the corresponding N- and O-arylated products in very high yields. The regioselectivity of unsymmetrical arynes has also been studied. A lot of useful, functional groups can tolerate our reaction conditions. Carbazoles and dibenzofurans are important heteroaromatic compounds, which have a variety of biological activities. A variety of substituted carbazoles and dibenzofwans are readily prepared in good to excellent yields starting with the corresponding o-iodoanilines or o-iodophenols and o-silylaryl triflates by a treatment with CsF, followed by a Pd-catalyzed cyclization, which overall provides a one-pot, two-step process. By using this methodology, the carbazole alkaloid mukonine has been concisely synthesized in a very good yield. Insertion of an aryne into a σ-bond between a nucleophile and an electrophile (Nu-E) should potentially be a very beneficial process from the standpoint of organic synthesis. A variety of substituted ketones and sulfoxides have been synthesized in good

  16. Genus Pouteria: chemistry and biological activity

    Directory of Open Access Journals (Sweden)

    Cíntia A. M. Silva

    Full Text Available The genus Pouteria belongs to the family Sapotaceae and can be widely found around the World. These plants have been used as building material, as food, because the eatable fruits, as well as remedies in folk medicine. Some biological activities have been reported to species of this genus such as antioxidant, anti-inflammatory, antibacterial and antifungal. However, the real potential of this genus as source of new drugs or phytomedicines remains unknown. Therefore, a review of the so far known chemical composition and biological activities of this genus is presented to stimulate new studies about the species already reported moreover that species have no reference about chemistry or biological activities could be found until now.

  17. Practical approaches to biological inorganic chemistry

    CERN Document Server

    Louro, Ricardo O

    2012-01-01

    The book reviews the use of spectroscopic and related methods to investigate the complex structures and mechanisms of biological inorganic systems that contain metals. Each chapter presents an overview of the technique including relevant theory, clearly explains what it is and how it works and then presents how the technique is actually used to evaluate biological structures. Practical examples and problems are included to illustrate each technique and to aid understanding. Designed for students and researchers who want to learn both the basics, and more advanced aspects of bioinorganic chemistry. It includes many colour illustrations enable easier visualization of molecular mechanisms and structures. It provides worked examples and problems that are included to illustrate and test the reader's understanding of each technique. It is written by a multi-author team who use and teach the most important techniques used today to analyse complex biological structures.

  18. Some conceptual issues in the transition from chemistry to biology.

    Science.gov (United States)

    Moreno, Alvaro

    2016-12-01

    The transition from chemistry to biology is an extremely complex issue because of the huge phenomenological differences between the two domains and because this transition has many different aspects and dimensions. In this paper, I will try to analyze how chemical systems have developed a cohesive, self-maintaining and functionally differentiated system that recruits its organization to stay far from equilibrium. This organization cannot exist but in an individualized form, and yet, it unfolds both a diachronic-historical and a synchronic collective dimension. I will argue that, far from being a problem, these different dimensions of the phenomenon of life, appear as a consequence of the nature of this individualized organization.

  19. Areas of research in radiation chemistry fundamental to radiation biology

    International Nuclear Information System (INIS)

    Powers, E.L.

    1980-01-01

    Among all the environmental hazards to which man is exposed, ionizing radiation is the most thoroughly investigated and the most responsibly monitored and controlled. Nevertheless, because of the importance of radiation in modern society from both the hazard as well as the utilitarian standpoints, much more information concerning the biological effects induced and their modification and reversal is required. Together with radiation physics, an understanding of radiation chemistry is necessary for full appreciation of biological effects of high and low energy radiations, and for the development of prophylactic, therapeutic and potentiating methods and techniques in biological organisms. The necessity of understanding the chemistry of any system, biological or not, that is to be manipulated and controlled, is so obvious as to make trivial a statement to that effect. If any natural phenomenon is to be put to our use, surely the elements of it must be studied and appreciated fully. In the preliminary statements of the various panels of this general group, the need for additional information on the basic radiation chemistry concerned in radiation-induced biological effects pervades throughout

  20. Russian science readings (chemistry, physics, biology)

    CERN Document Server

    Light, L

    1949-01-01

    Some years' experience in teaching Russian to working scientists who had already acquired the rudiments of the grammar convinced me of the need for a reader of the present type that would smooth the path of those wishing to study Russian scientific literature in the original. Although the subject matter comprises what I have described for convenience as chemistry, physics and biology, it could be read with equal profit by those engaged in any branch of pure or applied science. All the passages are taken from school textbooks, and acknowledgements are due to the authors of the works listed at the foot of the contents page.

  1. Chemistry and biology of insect bioluminescence

    International Nuclear Information System (INIS)

    Colepicolo Neto, P.; Bechara, E.J.H.

    1984-01-01

    Basic aspects on the Chemistry and Biology of bioluminescence are reviewed, with emphasis on insects. Data from the investigation of Lampyridae (fireflies) are collected from literature. With regard to Elateridae (click beetles) and Phengodidae (rail road worms), the least explored families of luminescent insects, new data are presented on the following aspects: (i) 'in vivo' emission spectra, (ii) chemical nature of the luciferin, (iii) conection between bioluminescence and 'oxygen toxicity' as a result of molecular oxygen storage and (iv) the role of light emission by larvae and pupae. (Author) [pt

  2. Physical organic chemistry in the making

    OpenAIRE

    Engberts, J.B.F.N.

    1997-01-01

    The discipline of physical organic chemistry will continue to occupy a central position in chemistry. The rapid increase in instrumentation and important theoretical developments allow the investigation of many problems of great complexity and challenge. In the next century the leading theme will continue to be the quantitative analysis of the effects of structural variation on the properties of molecules and molecular assemblies.

  3. Physical organic chemistry in the making

    NARCIS (Netherlands)

    Engberts, J.B.F.N.

    The discipline of physical organic chemistry will continue to occupy a central position in chemistry. The rapid increase in instrumentation and important theoretical developments allow the investigation of many problems of great complexity and challenge. In the next century the leading theme will

  4. A Colorful Solubility Exercise for Organic Chemistry

    Science.gov (United States)

    Shugrue, Christopher R.; Mentzen, Hans H., II; Linton, Brian R.

    2015-01-01

    A discovery chemistry laboratory has been developed for the introductory organic chemistry student to investigate the concepts of polarity, miscibility, solubility, and density. The simple procedure takes advantage of the solubility of two colored dyes in a series of solvents or solvent mixtures, and the diffusion of colors can be easily…

  5. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 1. Learning Organic Chemistry Through Natural Products Natural Products - A Kaleidoscopic View. N R Krishnaswamy. Series Article Volume 1 Issue 1 January 1996 pp 56-62 ...

  6. Organic chemistry - Fast reactions 'on water'

    NARCIS (Netherlands)

    Klijn, JE; Engberts, JBFN

    2005-01-01

    Efficient reactions in aqueous organic chemistry do not require soluble reactants, as had been thought. A newly developed ‘on-water’ protocol is characterized by short reaction times, and the products are easy to isolate.

  7. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Learning Organic Chemistry Through Natural Products Determination of Absolute Stereochemistry. N R Krishnaswamy. Series Article Volume 1 Issue 2 February 1996 pp 40-46 ...

  8. Newer Reagents in Preparative Organic Chemistry.

    Science.gov (United States)

    Grundy, J.

    1990-01-01

    Outlined is the development and use of oxidants for use in elementary organic chemistry classes. Discussed is the oxidation of alcohols to carbonyl compounds, and the oxidation of primary alcohols or aldehydes to carboxylic acids. (CW)

  9. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 12. Learning Organic Chemistry Through Natural Products - Architectural Designs in Molecular Constructions. N R Krishnaswamy. Volume 16 Issue 12 December 2011 pp 1287-1293 ...

  10. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 10. Learning Organic Chemistry Through Natural Products Architectural Designs in Molecular Constructions. N R Krishnaswamy. Series Article Volume 1 Issue 10 October 1996 pp 37-43 ...

  11. Organic chemistry in Titan's atmosphere

    Science.gov (United States)

    Scattergood, T.

    1982-01-01

    Laboratory photochemical simulations and other types of chemical simulations are discussed. The chemistry of methane, which is the major known constituent of Titan's atmosphere was examined with stress on what can be learned from photochemistry and particle irradiation. The composition of dust that comprises the haze layer was determined. Isotope fractionation in planetary atmospheres is also discussed.

  12. Radiation chemistry in development and research of radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2010-01-01

    During the establishment and development of radiation biology, radiation chemistry acts like bridge which units the spatial and temporal insight coming from radiation physics with radiation biology. The theory, model, and methodology of radiation chemistry play an important role in promoting research and development of radiation biology. Following research development of radiation biology effects towards systems radiation biology the illustration and exploration both diversity of biological responses and complex process of biological effect occurring remain to need the theory, model, and methodology come from radiation chemistry. (authors)

  13. Notions of radiation chemistry in biological systems

    International Nuclear Information System (INIS)

    Mastro, N.L. del.

    1989-10-01

    The present paper examines some aspects of the direct and indirect biological radiation effects: pair formation, free radicals, superoxide ion, hydrogen peroxide, hydroxyl radical, oxygen singlet together with the endogen radioprotector mechanisms of organisms and the ways in which an improved radioresistance of biochemical systems can be achieved. (author) [pt

  14. Nonlinear Oscillations in Biology and Chemistry

    CERN Document Server

    1986-01-01

    This volume contains the proceedings of a meeting entitled 'Nonlinear Oscillations in Biology and Chemistry', which was held at the University of Utah May 9-11,1985. The papers fall into four major categories: (i) those that deal with biological problems, particularly problems arising in cell biology, (ii) those that deal with chemical systems, (iii) those that treat problems which arise in neurophysiology, and (iv), those whose primary emphasis is on more general models and the mathematical techniques involved in their analysis. Except for the paper by Auchmuty, all are based on talks given at the meeting. The diversity of papers gives some indication of the scope of the meeting, but the printed word conveys neither the degree of interaction between the participants nor the intellectual sparks generated by that interaction. The meeting was made possible by the financial support of the Department of Mathe­ matics of the University of Utah. I am indebted to Ms. Toni Bunker of the Department of Mathematics for...

  15. The 'wired' universe of organic chemistry.

    Science.gov (United States)

    Grzybowski, Bartosz A; Bishop, Kyle J M; Kowalczyk, Bartlomiej; Wilmer, Christopher E

    2009-04-01

    The millions of reactions performed and compounds synthesized by organic chemists over the past two centuries connect to form a network larger than the metabolic networks of higher organisms and rivalling the complexity of the World Wide Web. Despite its apparent randomness, the network of chemistry has a well-defined, modular architecture. The network evolves in time according to trends that have not changed since the inception of the discipline, and thus project into chemistry's future. Analysis of organic chemistry using the tools of network theory enables the identification of most 'central' organic molecules, and for the prediction of which and how many molecules will be made in the future. Statistical analyses based on network connectivity are useful in optimizing parallel syntheses, in estimating chemical reactivity, and more.

  16. Titan: a laboratory for prebiological organic chemistry

    Science.gov (United States)

    Sagan, C.; Thompson, W. R.; Khare, B. N.

    1992-01-01

    When we examine the atmospheres of the Jovian planets (Jupiter, Saturn, Uranus, and Neptune), the satellites in the outer solar system, comets, and even--through microwave and infrared spectroscopy--the cold dilute gas and grains between the stars, we find a rich organic chemistry, presumably abiological, not only in most of the solar system but throughout the Milky Way galaxy. In part because the composition and surface pressure of the Earth's atmosphere 4 x 10(9) years ago are unknown, laboratory experiments on prebiological organic chemistry are at best suggestive; but we can test our understanding by looking more closely at the observed extraterrestrial organic chemistry. The present Account is restricted to atmospheric organic chemistry, primarily on the large moon of Saturn. Titan is a test of our understanding of the organic chemistry of planetary atmospheres. Its atmospheric bulk composition (N2/CH4) is intermediate between the highly reducing (H2/He/CH4/NH3/H2O) atmospheres of the Jovian planets and the more oxidized (N2/CO2/H2O) atmospheres of the terrestrial planets Mars and Venus. It has long been recognized that Titan's organic chemistry may have some relevance to the events that led to the origin of life on Earth. But with Titan surface temperatures approximately equal to 94 K and pressures approximately equal to 1.6 bar, the oceans of the early Earth have no ready analogue on Titan. Nevertheless, tectonic events in the water ice-rich interior or impact melting and slow re-freezing may lead to an episodic availability of liquid water. Indeed, the latter process is the equivalent of a approximately 10(3)-year-duration shallow aqueous sea over the entire surface of Titan.

  17. Integrated Chemistry and Biology for First-Year College Students

    Science.gov (United States)

    Abdella, Beth R. J.; Walczak, Mary M.; Kandl, Kim A.; Schwinefus, Jeffrey J.

    2011-01-01

    A three-course sequence for first-year students that integrates beginning concepts in biology and chemistry has been designed. The first two courses that emphasize chemistry and its capacity to inform biological applications are described here. The content of the first course moves from small to large particles with an emphasis on membrane…

  18. Wilson and Gisvold's textbook of organic medicinal and pharmaceutical chemistry

    National Research Council Canada - National Science Library

    Wilson, Charles Owens; Beale, John Marlowe; Block, John H

    2011-01-01

    "For over half a century, Wilson and Gisvold's Textbook of Organic Medicinal and Pharmaceutical Chemistry has served the discipline of medicinal chemistry for both graduate and undergraduate pharmacy...

  19. Organisational closure in biological organisms.

    Science.gov (United States)

    Mossio, Matteo; Moreno, Alvaro

    2010-01-01

    The central aim of this paper consists in arguing that biological organisms realize a specific kind of causal regime that we call "organisational closure"; i.e., a distinct level of causation, operating in addition to physical laws, generated by the action of material structures acting as constraints. We argue that organisational closure constitutes a fundamental property of biological systems since even its minimal instances are likely to possess at least some of the typical features of biological organisation as exhibited by more complex organisms. Yet, while being a necessary condition for biological organization, organisational closure underdetermines, as such, the whole set of requirements that a system has to satisfy in order to be taken as a paradigmatic example of organism. As we suggest, additional properties, as modular templates and control mechanisms via dynamical decoupling between constraints, are required to get the complexity typical of full-fledged biological organisms.

  20. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 9. Learning Organic Chemistry Through Natural Products A Practical Approach. N R Krishnaswamy. Series Article Volume 1 Issue 9 September 1996 pp 25-33. Fulltext. Click here to view fulltext PDF. Permanent link:

  1. Measuring Student Performance in General Organic Chemistry

    Science.gov (United States)

    Austin, Ara C.; Ben-Daat, Hagit; Zhu, Mary; Atkinson, Robert; Barrows, Nathan; Gould, Ian R.

    2015-01-01

    Student performance in general organic chemistry courses is determined by a wide range of factors including cognitive ability, motivation and cultural capital. Previous work on cognitive factors has tended to focus on specific areas rather than exploring performance across all problem types and cognitive skills. In this study, we have categorized…

  2. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 5. Learning Organic Chemistry Through Natural Products From Molecular and Electronic Structures to Reactivity. N R Krishnaswamy. Series Article Volume 1 Issue 5 May 1996 pp 12-18 ...

  3. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Learning Organic Chemistry Through Natural Products Determination of Absolute ... Author Affiliations. N R Krishnaswamy1. Visiting Professor, NMKRV College for Women with PG Centre, Jayanagar III Block, Bangalore 560011, India.

  4. Experimental interstellar organic chemistry - Preliminary findings

    Science.gov (United States)

    Khare, B. N.; Sagan, C.

    1973-01-01

    Review of the results of some explicit experimental simulation of interstellar organic chemistry consisting in low-temperature high-vacuum UV irradiation of condensed simple gases known or suspected to be present in the interstellar medium. The results include the finding that acetonitrile may be present in the interstellar medium. The implication of this and other findings are discussed.

  5. Mukilteo water sensor time series - Field work coupling measurements of carbon chemistry and distribution of free-living organisms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — To estimate the carbon chemistry conditions experienced by free-living organisms, we will conduct coupled biological/carbon chemistry sampling for key zooplankton...

  6. 2010 Tetrapyrroles, Chemistry & Biology of Gordon Research Conference

    Energy Technology Data Exchange (ETDEWEB)

    Angela Wilks

    2010-07-30

    The objective of the Chemistry & Biology of Tetrapyrroles Gordon Conference is to bring together researchers from diverse disciplines that otherwise would not interact. By bringing biologists, chemists, engineers and clinicians with a common interest in tetrapyrroles the conference provides a forum for cross-disciplinary ideas and collaboration. The perspective provided by biologists, chemists, and clinicians working in fields such as newly discovered defects in human porphyrin metabolism, the myriad of strategies for light harvesting in photosynthetic organisms, novel tetrapyrroles that serve as auxiliary chromophores or enzyme cofactors, synthetic strategies in the design of novel tetrapyrrole scaffolds, and tetrapyrrole based cell signaling and regulatory systems, makes this conference unique in the field. Over the years the growing evidence for the role of tetrapyrroles and their reactive intermediates in cell signaling and regulation has been of increasing importance at this conference. The 2010 conference on Chemistry & Biology of Tetrapyrroles will focus on many of these new frontiers as outlined in the preliminary program listed. Speakers will emphasize unpublished results and new findings in the field. The oral sessions will be followed by the highly interactive afternoon poster sessions. The poster sessions provide all conferees with the opportunity to present their latest research and to exchange ideas in a more informal setting. As in the past, this opportunity will continue during the nightly social gathering that takes place in the poster hall following the evening lectures. All conferees are encouraged to submit and present posters. At the conference the best poster in the areas of biology, chemistry and medicine will be selected by a panel of previous conference chairs.

  7. Medicinal plants from Mali: Chemistry and biology.

    Science.gov (United States)

    Wangensteen, Helle; Diallo, Drissa; Paulsen, Berit Smestad

    2015-12-24

    Mali is one of the countries in West Africa where the health system rely the most on traditional medicine. The healers are mainly using medicinal plants for their treatments. The studies performed being the basis for this review is of importance as they will contribute to sustaining the traditional knowledge. They contribute to evaluate and improve locally produced herbal remedies, and the review gives also an overview of the plant preparations that will have the most potential to be evaluated for new Improved Traditional Medicines. The aim of this review is to give an overview of the studies performed related to medicinal plants from Mali in the period 1995-2015. These studies include ethnopharmacology, chemistry and biological studies of the plants that were chosen based on our interviews with the healers in different regions of Mali, and contribute to sustainable knowledge on the medicinal plants. The Department of Traditional Medicine, Bamako, Mali, is responsible for registering the knowledge of the traditional healers on their use of medicinal plants and also identifying compounds in the plants responsible for the bioactivities claimed. The studies reported aimed at getting information from the healers on the use of medicinal plants, and study the biology and chemistry of selected plants for the purpose of verifying the traditional use of the plants. These studies should form the basis for necessary knowledge for the development of registered Improved Traditional Medicines in Mali. The healers were the ethnopharmacological informants. Questions asked initially were related to wound healing. This was because the immune system is involved when wounds are healed, and additionally the immune system is involved in the majority of the illnesses common in Mali. Based on the results of the interviews the plant material for studies was selected. Studies were performed on the plant parts the healers were using when treating their patients. Conventional chromatographic

  8. Experimental interstellar organic chemistry: Preliminary findings

    Science.gov (United States)

    Khare, B. N.; Sagan, C.

    1971-01-01

    In a simulation of interstellar organic chemistry in dense interstellar clouds or on grain surfaces, formaldehyde, water vapor, ammonia and ethane are deposited on a quartz cold finger and ultraviolet-irradiated in high vacuum at 77K. The HCHO photolytic pathway which produces an aldehyde radical and a superthermal hydrogen atom initiates solid phase chain reactions leading to a range of new compounds, including methanol, ethanol, acetaldehyde, acetonitrile, acetone, methyl formate, and possibly formic acid. Higher nitriles are anticipated. Genetic relations among these interstellar organic molecules (e.g., the Cannizzaro and Tischenko reactions) must exist. Some of them, rather than being synthesized from smaller molecules, may be degradation products of larger organic molecules, such as hexamethylene tetramine, which are candidate consitituents of the interstellar grains. The experiments reported here may also be relevant to cometary chemistry.

  9. The Eighth Central European Conference "Chemistry towards Biology": Snapshot.

    Science.gov (United States)

    Perczel, András; Atanasov, Atanas G; Sklenář, Vladimír; Nováček, Jiří; Papoušková, Veronika; Kadeřávek, Pavel; Žídek, Lukáš; Kozłowski, Henryk; Wątły, Joanna; Hecel, Aleksandra; Kołkowska, Paulina; Koča, Jaroslav; Svobodová-Vařeková, Radka; Pravda, Lukáš; Sehnal, David; Horský, Vladimír; Geidl, Stanislav; Enriz, Ricardo D; Matějka, Pavel; Jeništová, Adéla; Dendisová, Marcela; Kokaislová, Alžběta; Weissig, Volkmar; Olsen, Mark; Coffey, Aidan; Ajuebor, Jude; Keary, Ruth; Sanz-Gaitero, Marta; van Raaij, Mark J; McAuliffe, Olivia; Waltenberger, Birgit; Mocan, Andrei; Šmejkal, Karel; Heiss, Elke H; Diederich, Marc; Musioł, Robert; Košmrlj, Janez; Polański, Jarosław; Jampílek, Josef

    2016-10-17

    The Eighth Central European Conference "Chemistry towards Biology" was held in Brno, Czech Republic, on August 28-September 1, 2016 to bring together experts in biology, chemistry and design of bioactive compounds; promote the exchange of scientific results, methods and ideas; and encourage cooperation between researchers from all over the world. The topics of the conference covered "Chemistry towards Biology", meaning that the event welcomed chemists working on biology-related problems, biologists using chemical methods, and students and other researchers of the respective areas that fall within the common scope of chemistry and biology. The authors of this manuscript are plenary speakers and other participants of the symposium and members of their research teams. The following summary highlights the major points/topics of the meeting.

  10. Organic Chemistry in Action! What Is the Reaction?

    Science.gov (United States)

    O'Dwyer, Anne; Childs, Peter

    2015-01-01

    The "Organic Chemistry in Action!" ("OCIA!") program is a set of teaching resources designed to facilitate the teaching and learning of introductory level organic chemistry. The "OCIA!" program was developed in collaboration with practicing and experienced chemistry teachers, using findings from Chemistry Education…

  11. Titan's organic chemistry: Results of simulation experiments

    Science.gov (United States)

    Sagan, Carl; Thompson, W. Reid; Khare, Bishun N.

    1992-01-01

    Recent low pressure continuous low plasma discharge simulations of the auroral electron driven organic chemistry in Titan's mesosphere are reviewed. These simulations yielded results in good accord with Voyager observations of gas phase organic species. Optical constants of the brownish solid tholins produced in similar experiments are in good accord with Voyager observations of the Titan haze. Titan tholins are rich in prebiotic organic constituents; the Huygens entry probe may shed light on some of the processes that led to the origin of life on Earth.

  12. The Distribution of Macromolecular Principles throughout Introductory Organic Chemistry

    Science.gov (United States)

    Shulman, Joel I.

    2017-01-01

    Many of the principles of organic polymer chemistry are direct extensions of the information contained in the standard introductory organic chemistry course. Often, however, the discussion of macromolecules is relegated to a chapter at the end of the organic chemistry text and is covered briefly, if at all. Connecting the organic-chemical…

  13. Impact of Theoretical Chemistry on Chemical and Biological Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 19; Issue 4. Impact of Theoretical Chemistry on Chemical and Biological Sciences: Chemistry Nobel Prize – 2013. Saraswathi Vishveshwara. General Article Volume 19 Issue 4 April 2014 pp 347-367 ...

  14. AINSE conference on radiation biology and chemistry. Conference handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The conference handbook contains 60 oral and poster presentations dealing with recent advances in radiation chemistry applied to biological studies, radiopharmaceuticals, radiosensitizers as well as to solid state chemical physics.

  15. AINSE conference on radiation biology and chemistry. Conference handbook

    International Nuclear Information System (INIS)

    1994-01-01

    The conference handbook contains 60 oral and poster presentations dealing with recent advances in radiation chemistry applied to biological studies, radiopharmaceuticals, radiosensitizers as well as to solid state chemical physics

  16. High Structure Active Learning Pedagogy for the Teaching of Organic Chemistry: Assessing the Impact on Academic Outcomes

    Science.gov (United States)

    Crimmins, Michael T.; Midkiff, Brooke

    2017-01-01

    Organic Chemistry is a required course for programs in chemistry, biology, and many health science careers. It has historically been considered a highly challenging course with significant failure rates. As with many science disciplines, the teaching of Organic Chemistry has traditionally focused on unstructured exposition-centered delivery of…

  17. Stable States of Biological Organisms

    Science.gov (United States)

    Yukalov, V. I.; Sornette, D.; Yukalova, E. P.; Henry, J.-Y.; Cobb, J. P.

    2009-04-01

    A novel model of biological organisms is advanced, treating an organism as a self-consistent system subject to a pathogen flux. The principal novelty of the model is that it describes not some parts, but a biological organism as a whole. The organism is modeled by a five-dimensional dynamical system. The organism homeostasis is described by the evolution equations for five interacting components: healthy cells, ill cells, innate immune cells, specific immune cells, and pathogens. The stability analysis demonstrates that, in a wide domain of the parameter space, the system exhibits robust structural stability. There always exist four stable stationary solutions characterizing four qualitatively differing states of the organism: alive state, boundary state, critical state, and dead state.

  18. MIANN models in medicinal, physical and organic chemistry.

    Science.gov (United States)

    González-Díaz, Humberto; Arrasate, Sonia; Sotomayor, Nuria; Lete, Esther; Munteanu, Cristian R; Pazos, Alejandro; Besada-Porto, Lina; Ruso, Juan M

    2013-01-01

    Reducing costs in terms of time, animal sacrifice, and material resources with computational methods has become a promising goal in Medicinal, Biological, Physical and Organic Chemistry. There are many computational techniques that can be used in this sense. In any case, almost all these methods focus on few fundamental aspects including: type (1) methods to quantify the molecular structure, type (2) methods to link the structure with the biological activity, and others. In particular, MARCH-INSIDE (MI), acronym for Markov Chain Invariants for Networks Simulation and Design, is a well-known method for QSAR analysis useful in step (1). In addition, the bio-inspired Artificial-Intelligence (AI) algorithms called Artificial Neural Networks (ANNs) are among the most powerful type (2) methods. We can combine MI with ANNs in order to seek QSAR models, a strategy which is called herein MIANN (MI & ANN models). One of the first applications of the MIANN strategy was in the development of new QSAR models for drug discovery. MIANN strategy has been expanded to the QSAR study of proteins, protein-drug interactions, and protein-protein interaction networks. In this paper, we review for the first time many interesting aspects of the MIANN strategy including theoretical basis, implementation in web servers, and examples of applications in Medicinal and Biological chemistry. We also report new applications of the MIANN strategy in Medicinal chemistry and the first examples in Physical and Organic Chemistry, as well. In so doing, we developed new MIANN models for several self-assembly physicochemical properties of surfactants and large reaction networks in organic synthesis. In some of the new examples we also present experimental results which were not published up to date.

  19. Modified spiral organic curriculum on organic chemistry courses for chemistry education undergraduate students

    Science.gov (United States)

    Fauzi'ah, Lina; Diniaty, Artina; Arlianty, Widinda Normalia; Febriana, Beta Wulan

    2017-12-01

    This study aimed to know the effect of implementation modified spiral (or two-cycle) organic curriculum for Chemistry Education Undergraduate Students. The changing of curriculum that impacted in the organization of topics, was due to the low of student's achievement in Organic Chemistry courses. In a spiral curriculum, the first cycle was surveyed course which students learned about general organic chemistry that must be studied in year-long courses in the previous curriculum. The survey course discussed topics in less detail but with some emphasis on the topics that related to the chemistry for high school. The second course was the spiral of the first cycle that discussed the same chapter but in a more advanced discussion. In this cycle, students began to study about stereochemistry, mechanism of organic reaction and its application for daily need and industry. From the data analysis, there was a significant difference of students' achievement that learned with previous and spiral organic curriculum. It can be concluded that this modified curriculum is more appropriate to be applied for Chemistry Education students.

  20. Synthesis-Spectroscopy Roadmap Problems: Discovering Organic Chemistry

    Science.gov (United States)

    Kurth, Laurie L.; Kurth, Mark J.

    2014-01-01

    Organic chemistry problems that interrelate and integrate synthesis with spectroscopy are presented. These synthesis-spectroscopy roadmap (SSR) problems uniquely engage second-year undergraduate organic chemistry students in the personal discovery of organic chemistry. SSR problems counter the memorize-or-bust strategy that many students tend to…

  1. Organic Chemistry Self Instructional Package 15: Benzene, Aromaticity.

    Science.gov (United States)

    Zdravkovich, V.

    This booklet, one of a series of 17 developed at Prince George's Community College, Largo, Maryland, provides an individualized, self-paced undergraduate organic chemistry instruction module designed to augment any course in organic chemistry but particularly those taught using the text "Organic Chemistry" by Morrison and Boyd. The…

  2. Natural product synthesis at the interface of chemistry and biology.

    Science.gov (United States)

    Hong, Jiyong

    2014-08-11

    Nature has evolved to produce unique and diverse natural products that possess high target affinity and specificity. Natural products have been the richest sources for novel modulators of biomolecular function. Since the chemical synthesis of urea by Wöhler, organic chemists have been intrigued by natural products, leading to the evolution of the field of natural product synthesis over the past two centuries. Natural product synthesis has enabled natural products to play an essential role in drug discovery and chemical biology. With the introduction of novel, innovative concepts and strategies for synthetic efficiency, natural product synthesis in the 21st century is well poised to address the challenges and complexities faced by natural product chemistry and will remain essential to progress in biomedical sciences. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Electron Transfer in Chemistry and Biology - The Primary Events in ...

    Indian Academy of Sciences (India)

    electron transfer. (PET) is a very important process, with considerable chemical and biological relevance. GENERAL I ARTICLE of electrons, respectively. This has entirely changed the earlier framework of interpreting reactions in chemistry and biology. This shift in emphasis enables one to understand the elementary.

  4. Electron Transfer in Chemistry and Biology - The Primary Events in ...

    Indian Academy of Sciences (India)

    Electron Transfer in Chemistry and Biology -. The Primary Events in Photosynthesis. V Krishnan. One of the most important chemical reactions is electron transfer from one atomic/molecular unit to another. This reaction, accompanied by proton and hydrogen atom transfers, occurs in a cascade in many biological processes,.

  5. Impact of Theoretical Chemistry on Chemical and Biological Sciences

    Indian Academy of Sciences (India)

    IAS Admin

    molecular dynamics simulations and graph theory as applied to biological systems. Her group has developed network approaches to investigate functionally important amino acids in protein structures. Keywords. Quantum Chemistry, molecular mechanics, force fields, QM/MM hybrid method, systems biology, molecular ...

  6. Atmospheric Chemistry of Micrometeoritic Organic Compounds

    Science.gov (United States)

    Kress, M. E.; Belle, C. L.; Pevyhouse, A. R.; Iraci, L. T.

    2011-01-01

    Micrometeorites approx.100 m in diameter deliver most of the Earth s annual accumulation of extraterrestrial material. These small particles are so strongly heated upon atmospheric entry that most of their volatile content is vaporized. Here we present preliminary results from two sets of experiments to investigate the fate of the organic fraction of micrometeorites. In the first set of experiments, 300 m particles of a CM carbonaceous chondrite were subject to flash pyrolysis, simulating atmospheric entry. In addition to CO and CO2, many organic compounds were released, including functionalized benzenes, hydrocarbons, and small polycyclic aromatic hydrocarbons. In the second set of experiments, we subjected two of these compounds to conditions that simulate the heterogeneous chemistry of Earth s upper atmosphere. We find evidence that meteor-derived compounds can follow reaction pathways leading to the formation of more complex organic compounds.

  7. Analytical Chemistry at the Interface Between Materials Science and Biology

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Janese C. [Iowa State Univ., Ames, IA (United States)

    2000-09-21

    Likedlessentid sciences, anal~cd chetis~continues toreinvent itself. Moving beyond its traditional roles of identification and quantification, analytical chemistry is now expanding its frontiers into areas previously reserved to other disciplines. This work describes several research efforts that lie at the new interfaces between analytical chemistry and two of these disciplines, namely materials science and biology. In the materials science realm, the search for new materials that may have useful or unique chromatographic properties motivated the synthesis and characterization of electrically conductive sol-gels. In the biology realm, the search for new surface fabrication schemes that would permit or even improve the detection of specific biological reactions motivated the design of miniaturized biological arrays. Collectively, this work represents some of analytical chemistry’s newest forays into these disciplines. The introduction section to this dissertation provides a literature review on several of the key aspects of this work. In advance of the materials science discussion, a brief introduction into electrochemically-modulated liquid chromatography (EMLC) and sol-gel chemistry is provided. In advance of the biological discussions, brief overviews of scanning force microscopy (SFM) and the oxidative chemistry used to construct our biological arrays are provided. This section is followed by four chapters, each of which is presented as a separate manuscript, and focuses on work that describes some of our cross-disciplinary efforts within materials science and biology. This dissertation concludes with a general summary and future prospectus.

  8. Investigating Students' Similarity Judgments in Organic Chemistry

    Science.gov (United States)

    Graulich, N.; Bhattacharyya, G.

    2017-01-01

    Organic chemistry is possibly the most visual science of all chemistry disciplines. The process of scientific inquiry in organic chemistry relies on external representations, such as Lewis structures, mechanisms, and electron arrows. Information about chemical properties or driving forces of mechanistic steps is not available through direct…

  9. Organic Chemistry in Action! Developing an Intervention Program for Introductory Organic Chemistry to Improve Learners' Understanding, Interest, and Attitudes

    Science.gov (United States)

    O'Dwyer, Anne; Childs, Peter

    2014-01-01

    The main areas of difficulty experienced by those teaching and learning organic chemistry at high school and introductory university level in Ireland have been identified, and the findings support previous studies in Ireland and globally. Using these findings and insights from chemistry education research (CER), the Organic Chemistry in Action!…

  10. Chemistry and Biology of Orexin Signaling

    OpenAIRE

    Kodadek, Thomas; Cai, Di

    2010-01-01

    The orexins are neurohormones that, in concert with their cognate receptors, regulate a number of important physiological processes, including feeding, sleep, reward seeking and energy homeostasis. The orexin receptors have recently emerged as important drug targets. This review provides an overview of recent development in deciphering the biology of orexin signaling as well as efforts to manipulate orexin signaling pharmacologically.

  11. Dragonfly: In Situ Exploration of Titan's Organic Chemistry and Habitability

    Science.gov (United States)

    Turtle, E. P.; Barnes, J. W.; Trainer, M. G.; Lorenz, R. D.

    2017-12-01

    Titan's abundant complex carbon-rich chemistry, interior ocean, and past presence of liquid water on the surface make it an ideal destination to study prebiotic chemical processes and document the habitability of an extraterrestrial environment. Titan exploration is a high science priority due to the level of organic synthesis that it supports. Moreover, opportunities for organics to have interacted with liquid water at the surface (e.g., in impact melt sheets) increase the potential for chemical processes to progress further, providing an unparalleled opportunity to investigate prebiotic chemistry, as well as to search for signatures of potential water-based or even hydrocarbon-based life. The diversity of Titan's surface materials and environments drives the scientific need to be able to sample a variety of locations, thus mobility is key for in situ measurements. Titan's atmosphere is 4 times denser than Earth's reducing the wing/rotor area required to generate a given amount of lift, and the low gravity reduces the required magnitude of lift, making heavier-than-air mobility highly efficient. Dragonfly is a rotorcraft lander mission proposed to NASA's New Frontiers Program to take advantage of Titan's unique natural laboratory to understand how far chemistry can progress in environments that provide key ingredients for life. Measuring the compositions of materials in different environments will reveal how far organic chemistry has progressed. Surface material can be sampled into a mass spectrometer to identify the chemical components available and processes at work to produce biologically relevant compounds. Bulk elemental surface composition can be determined by a neutron-activated gamma-ray spectrometer. Meteorology measurements can characterize Titan's atmosphere and diurnal and spatial variations therein. Geologic features can be characterized via remote-sensing observations, which also provide context for samples. Seismic sensing can probe subsurface

  12. Atmospheric Prebiotic Chemistry and Organic Hazes

    Science.gov (United States)

    Trainer, Melissa G.

    2012-01-01

    Earth's atmospheric composition at the time of the origin of life is not known, but it has often been suggested that chemical transformation of reactive species in the atmosphere was a significant source of pre biotic organic molecules. Experimental and theoretical studies over the past half century have shown that atmospheric synthesis can yield molecules such as amino acids and nucleobases, but these processes are very sensitive to gas composition and energy source. Abiotic synthesis of organic molecules is more productive in reduced atmospheres, yet the primitive Earth may not have been as reducing as earlier workers assumed, and recent research has reflected this shift in thinking. This work provides a survey of the range of chemical products that can be produced given a set of atmospheric conditions, with a particular focus on recent reports. Intertwined with the discussion of atmospheric synthesis is the consideration of an organic haze layer, which has been suggested as a possible ultraviolet shield on the anoxic early Earth. Since such a haze layer - if formed - would serve as a reservoir for organic molecules, the chemical composition of the aerosol should be closely examined. The results highlighted here show that a variety of products can be formed in mildly reducing or even neutral atmospheres, demonstrating that contributions of atmospheric synthesis to the organic inventory on early Earth should not be discounted. This review intends to bridge current knowledge of the range of possible atmospheric conditions in the prebiotic environment and pathways for synthesis under such conditions by examining the possible products of organic chemistry in the early atmosphere.

  13. At the Intersection of Chemistry, Biology, and Medicine.

    Science.gov (United States)

    Walsh, Christopher T

    2017-06-20

    After an undergraduate degree in biology at Harvard, I started graduate school at The Rockefeller Institute for Medical Research in New York City in July 1965. I was attracted to the chemical side of biochemistry and joined Fritz Lipmann's large, hierarchical laboratory to study enzyme mechanisms. That work led to postdoctoral research with Robert Abeles at Brandeis, then a center of what, 30 years later, would be called chemical biology. I spent 15 years on the Massachusetts Institute of Technology faculty, in both the Chemistry and Biology Departments, and then 26 years on the Harvard Medical School Faculty. My research interests have been at the intersection of chemistry, biology, and medicine. One unanticipated major focus has been investigating the chemical logic and enzymatic machinery of natural product biosynthesis, including antibiotics and antitumor agents. In this postgenomic era it is now recognized that there may be from 10 5 to 10 6 biosynthetic gene clusters as yet uncharacterized for potential new therapeutic agents.

  14. Understanding the Impact of a General Chemistry Course on Students' Transition to Organic Chemistry

    Science.gov (United States)

    Collins-Webb, Alexandra; Jeffery, Kathleen A.; Sweeder, Ryan D.

    2016-01-01

    The move from general chemistry to organic chemistry can be a challenge for students as it often involves a transition from quantitatively-oriented to mechanistically-oriented thinking. This study found that the design of the general chemistry course can change the student experience of this transition as assessed by a reflective survey. The…

  15. Cocrystal Controlled Solid-State Synthesis: A Green Chemistry Experiment for Undergraduate Organic Chemistry

    Science.gov (United States)

    Cheney, Miranda L.; Zaworotko, Michael J.; Beaton, Steve; Singer, Robert D.

    2008-01-01

    Green chemistry has become an important area of concern for all chemists from practitioners in the pharmaceutical industry to professors and the students they teach and is now being incorporated into lectures of general and organic chemistry courses. However, there are relatively few green chemistry experiments that are easily incorporated into…

  16. Criegee Chemistry on Aqueous Organic Surfaces.

    Science.gov (United States)

    Enami, Shinichi; Colussi, A J

    2017-04-06

    In the troposphere, the fate of gas-phase Criegee intermediates (CIs) is deemed to be determined by their reactions with water molecules. Here it is shown that CIs produced in situ on the surface of water/acetonitrile (W/AN) solutions react competitively with millimolar carboxylic acids. Present experiments probe, via online electrospray mass spectrometry, CIs' chemistry on the surface of α-humulene and β-caryophyllene in W/AN microjets exposed to O 3 (g) for competitiveness being an increasing function of n. Present findings demonstrate that CIs can react with species other than H 2 O on the surface of aqueous organic aerosols due to the low water concentrations prevalent in the outermost interfacial layers.

  17. A tracer aided study on silicon chemistry in biological systems

    NARCIS (Netherlands)

    Brasser, H.J.

    2009-01-01

    Silicon (Si) is omnipresent in nature, and it is involved in important but diverse roles in a broad range of organisms, including diatoms, higher plants and humans. Some organisms, like the diatoms, need high amounts of silicon, and master silicon chemistry to a high extend using several enzymes.

  18. Practicing What We Preach: Assessing "Critical Thinking" in Organic Chemistry

    Science.gov (United States)

    Stowe, Ryan L.; Cooper, Melanie M.

    2017-01-01

    Organic chemistry is often promoted as a course designed to cultivate skill in scientific "ways of thinking." Expert organic chemists perceive their field as one in which plausible answers to complex questions are arrived at through analytical thought processes. They draw analogy between problem solving in organic chemistry and diagnosis…

  19. Benchmarking Problems Used in Second Year Level Organic Chemistry Instruction

    Science.gov (United States)

    Raker, Jeffrey R.; Towns, Marcy H.

    2010-01-01

    Investigations of the problem types used in college-level general chemistry examinations have been reported in this Journal and were first reported in the "Journal of Chemical Education" in 1924. This study extends the findings from general chemistry to the problems of four college-level organic chemistry courses. Three problem…

  20. Lewisite: its chemistry, toxicology, and biological effects.

    Science.gov (United States)

    Goldman, M; Dacre, J C

    1989-01-01

    Lewisite is an organic arsenical war gas which is a vesicant with attendant toxicities due to its ability to combine with thiol groups which are essential for activity of a variety of enzymes. Although Lewisite has been designated as a "suspected carcinogen," the indictment is not supported by the available scientific evidence. Indeed, the unwarranted conclusion is based on one specific case history of a former German soldier whose lower right leg was exposed to liquid Lewisite in 1940 with subsequent development of intraepidermal squamous cell carcinoma, and the examination of death certificates of former workers at a Japanese factory that manufactured a variety of war gases including mustard gas, hydrocyanic acid, chloracetophenome, phosgene, diphenylcyanarsine and Lewisite. It is difficult to comprehend why Lewisite was selected out of this group of toxic chemicals as one of those responsible for respiratory cancer in these workers. It would appear to be a difficult task, indeed, to disengage a specific worker from one of the other of several gases at the workplace and assign a specific gas-induced death. The evidence that organic arsenicals are carcinogenic is weak. Although the weight of evidence is such that inorganic arsenical derivatives are considered weak mutagens, the evidence that organic arsenicals are mutagenic is poor. Recent examination of the mutagenic potential of Lewisite using the Ames test has shown that Lewisite is not mutagenic under these circumstances. While oral administration of arsenical compounds, whether inorganic or organic, does not induce teratogenicity except at very high dose levels which are associated with some degree of maternal toxicity, parenteral administration has been associated with teratogenicity but information of maternal toxicity has not always been available. Indeed, maternal toxicity should be considered as an important diagnostic tool in assessing whether a chemical is teratogenic. The significance of parenteral

  1. Emerging trends at the interface of chemistry and biology ...

    Indian Academy of Sciences (India)

    This article describes recent developments in the design and implementation of various strategies towards the development of novel therapeutics using first principles from biology and chemistry. Strategies for multi-target therapeutics and network analysis with a focus on cancer and HIV are discussed. Methods for gene ...

  2. Emerging trends at the interface of Chemistry and Biology ...

    Indian Academy of Sciences (India)

    This article describes recent developments in the design and implementation of various strategies towards the development of novel therapeutics using first principles from biology and chemistry. Strategies for multi-target therapeutics and network analysis with a focus on cancer and HIV are discussed. Methods for gene ...

  3. The chemistry and biology of guanidine natural products.

    Science.gov (United States)

    Berlinck, Roberto G S; Bertonha, Ariane F; Takaki, Mirelle; Rodriguez, Julie P G

    2017-11-15

    Covering: 2015 and 2016The chemistry and biology of natural guanidines isolated from microbial culture media, from marine invertebrates, as well as from terrestrial plants and animals, are reviewed. Emphasis is directed to the biosynthesis, total synthesis, ecological roles as well as on the evolution of guanidines isolated from natural sources.

  4. Outstanding marine molecules : chemistry, biology, analysis

    OpenAIRE

    Debitus, Cécile; Kornprobst, J.M.

    2014-01-01

    Stalked crinoids were, for a long time, known as fossils found in different quarries, and also from ocean depths since the great expeditions of the eighteenth century. The chemical analyses of fossils and also of living organisms led to the discovery of new bioactive pigments, and also confirmed that the core structures of these pigments had been preserved during the fossilization process. The existence of these quinoid pigments also leads to several interesting questions related to ...

  5. The chemistry and biology of mycolactones

    Directory of Open Access Journals (Sweden)

    Matthias Gehringer

    2017-08-01

    Full Text Available Mycolactones are a group of macrolides excreted by the human pathogen Mycobacterium ulcerans, which exhibit cytotoxic, immunosuppressive and analgesic properties. As the virulence factor of M. ulcerans, mycolactones are central to the pathogenesis of the neglected disease Buruli ulcer, a chronic and debilitating medical condition characterized by necrotic skin ulcers. Due to their complex structure and fascinating biology, mycolactones have inspired various total synthesis endeavors and structure–activity relationship studies. Although this review intends to cover all synthesis efforts in the field, special emphasis is given to the comparison of conceptually different approaches and to the discussion of more recent contributions. Furthermore, a detailed discussion of molecular targets and structure–activity relationships is provided.

  6. How does biology emerge from chemistry?

    DEFF Research Database (Denmark)

    Wieczorek, Rafal

    2012-01-01

    Proper theory for the origins-of-life should propose a logical chain of events that would start with prebiotic soup and end with a living organism. RNA-world seems to be the only theory for the origin-of-life that succeeds at this task. Despite heavy criticism directed at it no alternative theories...... of similar scope have been put forward. This talk will be an attempt at providing an alternative theory for the origin-of-life based on the so called “compartmentalistic school” approach. We will start by the premise of prebiotic-ecology, in which complex molecules of prebiotic soup interact with each other...... giving rise to supramolecular-selection, a process in which different macromolecular assemblies are preferentially formed basing on their contingent properties. The second premise will be a spontaneous appearance of autopoietic entities trough the actions of supramolecular selection. It will be argued...

  7. Joining Forces: The Chemical Biology-Medicinal Chemistry Continuum.

    Science.gov (United States)

    Plowright, Alleyn T; Ottmann, Christian; Arkin, Michelle; Auberson, Yves P; Timmerman, Henk; Waldmann, Herbert

    2017-09-21

    The scientific advances being made across all disciplines are creating ever-increasing opportunities to enhance our knowledge of biological systems and how they relate to human disease. One of the central driving forces in discovering new medicines is medicinal chemistry, where the design and synthesis of novel compounds has led to multiple drugs. Chemical biology, sitting at the interface of many disciplines, has now emerged as a major contributor to the understanding of biological systems and is becoming an integral part of drug discovery. Bringing chemistry and biology much closer and blurring the boundaries between disciplines is creating new opportunities to probe and understand biology; both disciplines play key roles and need to join forces and work together effectively to synergize their impact. The power of chemical biology will then reach its full potential and drive innovation, leading to the discovery of transformative medicines to treat patients. Advances in cancer biology and drug discovery highlight this potential. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The 2010 Chemistry Nobel Prize: Pd(0)-Catalyzed Organic Synthesis

    Indian Academy of Sciences (India)

    mechanistic organic chemistry, and clay- catalysed organic reactions (Green. Chemistry). (right) Sunil Kumar is a PhD from Mysore. University. He has the industrial experience of working in Syngene. (Biocon) and has worked as post doctoral fellow at the Indian. Institute of Science,. Bangalore before joining Jain University,.

  9. Who Says Organic Chemistry Is Difficult? Exploring Perspectives and Perceptions

    Science.gov (United States)

    O'Dwyer, Anne; Childs, Peter E.

    2017-01-01

    Much research has identified organic chemistry as an area of difficulty for learners. There is also much literature pertaining to the factors that contribute to learners' difficulties. This paper explores the intersections of teachers' and learners' perceptions of teaching and learning organic chemistry respectively. Understanding these nuances…

  10. Students' Understanding of Alkyl Halide Reactions in Undergraduate Organic Chemistry

    Science.gov (United States)

    Cruz-Ramirez de Arellano, Daniel

    2013-01-01

    Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is…

  11. Azeotropic Preparation of a "C"-Phenyl "N"-Aryl Imine: An Introductory Undergraduate Organic Chemistry Laboratory Experiment

    Science.gov (United States)

    Silverberg, Lee J.; Coyle, David J.; Cannon, Kevin C.; Mathers, Robert T.; Richards, Jeffrey A.; Tierney, John

    2016-01-01

    Imines are important in biological chemistry and as intermediates in organic synthesis. An experiment for introductory undergraduate organic chemistry is presented in which benzaldehyde was condensed with "p"-methoxyaniline in toluene to give 4-methoxy-"N"-(phenylmethylene)benzenamine. Water was removed by azeotropic…

  12. A Comparison of How Undergraduates, Graduate Students, and Professors Organize Organic Chemistry Reactions

    Science.gov (United States)

    Galloway, Kelli R.; Leung, Min Wah; Flynn, Alison B.

    2018-01-01

    To explore the differences between how organic chemistry students and organic chemistry professors think about organic chemistry reactions, we administered a card sort task to participants with a range of knowledge and experience levels. Beginning students created a variety of categories ranging from structural similarities to process oriented…

  13. Flipping organic chemistry course: Possibilities and challenges

    Science.gov (United States)

    Cha, J.; Kim, H. B.

    2016-06-01

    The flipped classroom approach was applied to an introductory organic chemistry course. A total of 76 video clips (15 hours of running time) were developed and delivered to 41 sophomores (21 females and 20 males) through Youtube in addition to the university's learning management system. The students were asked to preview the lecture contents before each class by watching a pre-class video. For in-class activities, exercise problems were presented to groups of 3-5 students. An instructor and a teaching assistant guided each group to solve problems cooperatively, monitored the students’ group activity and answered their questions. At the end of every chapter, the students were asked to evaluate their group work and personal preparedness for the class and also to write a short reflective journal. The muddiest point of each chapter, i.e., the topic posing the most difficulty to students’ understanding, was surveyed through Google Forms®. The students liked watching the videos before each class and performing student-centered, in-class group activities but a few limitations were also found and reported.

  14. Stochasticity in processes fundamentals and applications to chemistry and biology

    CERN Document Server

    Schuster, Peter

    2016-01-01

    This book has developed over the past fifteen years from a modern course on stochastic chemical kinetics for graduate students in physics, chemistry and biology. The first part presents a systematic collection of the mathematical background material needed to understand probability, statistics, and stochastic processes as a prerequisite for the increasingly challenging practical applications in chemistry and the life sciences examined in the second part. Recent advances in the development of new techniques and in the resolution of conventional experiments at nano-scales have been tremendous: today molecular spectroscopy can provide insights into processes down to scales at which current theories at the interface of physics, chemistry and the life sciences cannot be successful without a firm grasp of randomness and its sources. Routinely measured data is now sufficiently accurate to allow the direct recording of fluctuations. As a result, the sampling of data and the modeling of relevant processes are doomed t...

  15. Mass spectrometry. [in organic ion and biorganic chemistry and medicine

    Science.gov (United States)

    Burlingame, A. L.; Cox, R. E.; Derrick, P. J.

    1974-01-01

    Review of the present status of mass spectrometry in the light of pertinent recent publications spanning the period from December 1971 to January 1974. Following an initial survey of techniques, instruments, and computer applications, a sharp distinction is made between the chemistry of organic (radical-)ions and analytical applications in biorganic chemistry and medicine. The emphasis is on the chemistry of organic (radical-)ions at the expense of inorganic, organometallic, and surface ion chemistry. Biochemistry and medicine are chosen because of their contemporary importance and because of the stupendous contributions of mass spectroscopy to these fields in the past two years. In the review of gas-phase organic ion chemistry, special attention is given to studies making significant contributions to the understanding of ion chemistry.

  16. Chemistry and Biology of the Caged Garcinia Xanthones

    Science.gov (United States)

    Chantarasriwong, Oraphin; Batova, Ayse; Chavasiri, Warinthorn

    2011-01-01

    Natural products have been a great source of many small molecule drugs for various diseases. In spite of recent advances in biochemical engineering and fermentation technologies that allow us to explore microorganisms and the marine environment as alternative sources of drugs, more than 70% of the current small molecule therapeutics derive their structures from plants used in traditional medicine. Natural-product-based drug discovery relies heavily on advances made in the sciences of biology and chemistry. Whereas biology aims to investigate the mode of action of a natural product, chemistry aims to overcome challenges related to its supply, bioactivity, and target selectivity. This review summarizes the explorations of the caged Garcinia xanthones, a family of plant metabolites that possess a unique chemical structure, potent bioactivities, and a promising pharmacology for drug design and development. PMID:20648491

  17. Contextualization and technologies in the Biology and Chemistry textbooks

    Directory of Open Access Journals (Sweden)

    Rozana Gomes de Abreu

    2005-12-01

    Full Text Available We analyze Biology and Chemistry school textbooks to understand how conceptions of contextualization and technologies are overtaken and hybridized. We consider that textbooks produce meanings (senses and signifieds in curricular policies. These are cultural productions that were hybridized and recontextualized according to Basil Bernstein and Stephen Ball. We argue that the focus on contextualization and technologies expressed in those textbooks are hybridized from several influences and they do not represent a consensus about those conceptions.

  18. Understanding recognition and self-assembly in biology using the chemist's toolbox. Insight into medicinal chemistry.

    Science.gov (United States)

    Quirolo, Z B; Benedini, L A; Sequeira, M A; Herrera, M G; Veuthey, T V; Dodero, V I

    2014-01-01

    Medicinal chemistry is intimately connected with basic science such as organic synthesis, chemical biology and biophysical chemistry among other disciplines. The reason of such connections is due to the power of organic synthesis to provide designed molecules; chemical biology to give tools to discover biological and/or pathological pathways and biophysical chemistry which provides the techniques to characterize and the theoretical background to understand molecular behaviour. The present review provides some selective examples of these research areas. Initially, template dsDNA organic synthesis and the spatio-temporal control of transcription are presenting following by the supramolecular entities used in drug delivery, such as liposomes and liquid crystal among others. Finally, peptides and protein self-assembly is connected with biomaterials and as an important event in the balance between health and disease. The final aim of the present review is to show the power of chemical tools not only for the synthesis of new molecules but also to improve our understanding of recognition and self-assembly in the biological context.

  19. 11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

    Directory of Open Access Journals (Sweden)

    Maria Emília Sousa

    2016-03-01

    Full Text Available For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report.

  20. 11th National Meeting of Organic Chemistry and 4th Meeting of Therapeutic Chemistry

    Science.gov (United States)

    Sousa, Maria Emília; Araújo, Maria João; do Vale, Maria Luísa; Andrade, Paula B.; Branco, Paula; Gomes, Paula; Moreira, Rui; Pinho e Melo, Teresa M.V.D.; Freitas, Victor

    2016-01-01

    For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report. PMID:27102166

  1. Modeling the Explicit Chemistry of Anthropogenic and Biogenic Organic Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Madronich, Sasha [Univ. Corporation for Atmospheric Research, Boulder, CO (United States)

    2015-12-09

    The atmospheric burden of Secondary Organic Aerosols (SOA) remains one of the most important yet uncertain aspects of the radiative forcing of climate. This grant focused on improving our quantitative understanding of SOA formation and evolution, by developing, applying, and improving a highly detailed model of atmospheric organic chemistry, the Generation of Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) model. Eleven (11) publications have resulted from this grant.

  2. Inorganic and organic radiation chemistry: state and problems

    International Nuclear Information System (INIS)

    Kalyazin, E.P.; Bugaenko, L.T.

    1990-01-01

    Radiation inorganic and organic chemistry is presented on the basis of the general scheme and classification of radiolysis products and elementary processes, by which evolution of radiation-affected substances up to the final radiolysis products takes place. The evolution is traced for the representatives of inorganic and organic compounds. The contribution of radiation inorganic and organic chemistry to radiation technology, radiation materials technology, radiation ecology and medicine, is shown. Tendencies in the development of radiation chemistry and prediction of its certain directions are considered

  3. Creatine Synthesis: An Undergraduate Organic Chemistry Laboratory Experiment

    Science.gov (United States)

    Smith, Andri L.; Tan, Paula

    2006-01-01

    Students in introductory chemistry classes typically appreciate seeing the connection between course content and the "real world". For this reason, we have developed a synthesis of creatine monohydrate--a popular supplement used in sports requiring short bursts of energy--for introductory organic chemistry laboratory courses. Creatine monohydrate…

  4. The biology and chemistry of the zoanthamine alkaloids.

    Science.gov (United States)

    Behenna, Douglas C; Stockdill, Jennifer L; Stoltz, Brian M

    2008-01-01

    Marine natural products have long played an important role in natural products chemistry and drug discovery. Mirroring the rich variety and complicated interactions of the marine environment, the substances isolated from sea creatures tend to be incredibly diverse in both molecular structure and biological activity. The natural products isolated from the polyps of marine zoanthids are no exception. The zoanthamine alkaloids, the first of which were isolated over 20 years ago, are of particular interest to the synthetic community because they feature a novel structural framework and exhibit a broad range of biological activities. In this Review, we summarize the major contributions to understanding the zoanthamine natural products with regard to their isolation and structure determination, as well as studies on their biological activity and total synthesis.

  5. Introduction to the Thematic Minireview Series: Green biological chemistry.

    Science.gov (United States)

    Jez, Joseph M

    2018-04-06

    Plants and their green cousins cyanobacteria and algae use sunlight to drive the chemistry that lets them grow, survive, and perform an amazing range of biochemical reactions. The ability of these organisms to use a freely available energy source makes them attractive as sustainable and renewable platforms for more than just food production. They are also a source of metabolic tools for engineering microbes for "green" chemistry. This Thematic Minireview Series discusses how green organisms capture light and protect their photosynthetic machinery from too much light; new structural snapshots of the clock complex that orchestrates signaling during the light/dark cycle; challenges for improving stress responses in crops; harnessing cyanobacteria as biofactories; and efforts to engineer microbes for "green" biopolymer production. © 2018 Jez.

  6. Aspects and prospects of the chemistry of organic heterocycles (review)

    International Nuclear Information System (INIS)

    Schroth, W.

    1986-01-01

    The systematics of heterocycles, their place in organic chemistry, and their significance for theory and practice are discussed. Problems of the chemistry of heterocycles are discussed on the examples of systems with various types of conjugation and ring sizes. The focus is on the principles of synthesis of heterocycles, in particular, those based on acetylene, various C 3 fragments, carbon disulfide, and maleic anhydride. Individual sections of the survey are devoted to the role of heterocycles in biosynthesis, as well as certain problems common to the chemistry of heterocycles, biochemistry, and macromolecular chemistry

  7. Charge Migration in DNA Perspectives from Physics, Chemistry, and Biology

    CERN Document Server

    Chakraborty, Tapash

    2007-01-01

    Charge migration through DNA has been the focus of considerable interest in recent years. A deeper understanding of the nature of charge transfer and transport along the double helix is important in fields as diverse as physics, chemistry and nanotechnology. It has also important implications in biology, in particular in DNA damage and repair. This book presents contributions from an international team of researchers active in this field. It contains a wide range of topics that includes the mathematical background of the quantum processes involved, the role of charge transfer in DNA radiation damage, a new approach to DNA sequencing, DNA photonics, and many others. This book should be of value to researchers in condensed matter physics, chemical physics, physical chemistry, and nanoscale sciences.

  8. Improvements to the Characterization of Organic Nitrogen Chemistry

    Science.gov (United States)

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  9. Evaluation of Learning Processes in an Organic Chemistry Course.

    Science.gov (United States)

    Maroto, B.; Camusso, C.; Cividini, M.

    1997-01-01

    Reviews a subjective exercise completed by students at the end of each of six units in an introductory organic chemistry course. Argues that instruction should be shaped by Ausubel's concept of meaningful learning. (DDR)

  10. Green chemistry principles in organic compound synthesis and analysis

    OpenAIRE

    Ruchi Verma; Lalit Kumar; Vijay Bhaskar Kurba

    2014-01-01

    The present review focus on various green chemistry approaches which could be utilized in the organic compounds in practical classes for undergraduate level in comparison of conventional methods. These methods avoid the usage of hazardous substances and are environmental friendly.

  11. Learning Organic Chemistry Through Natural Products -12 ...

    Indian Academy of Sciences (India)

    The leaves of this plant are tradi- tionally used for the treatment of jaundice and other liver dis- orders. like T R Seshadri and K. Venkataraman, T R Govinda- chari has also made significant contributions to the chemistry of natural products. He had his initial training from the Ameri- can chemist Roger Adams. Intramolecular.

  12. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    In order to keep the focus on chemistry, we defer giving its trivial name and plant source till the end of the discussion. An addi- ... The functional groups are to be determined now. The nature of the oxygen functionality is shown by a ... unaffected . SIRIIS I ARTICLI group since it undergoes acetylation. B moves higher with the.

  13. Looking forward: a glance into the future of organic chemistry

    International Nuclear Information System (INIS)

    Compain, Ph.; Desvergnes, V.; Suzenet, F.; Ollivier, C.; Robert, F.; Mihail, Barboiu; Belmont, Ph.; Bleriot, Y.; Bolze, F.; Bouquillon, S.; Bourguet, E.; Braida, B.; Constantieux, Th.; Desaubry, L.; Dupont, D.; Gastaldi, St.; Jerome, F.; Legoupy, St.; Marat, X.; Migaud, M.; Moitessier, N.; Papot, S.; Peri, F.; Petit, M.; Py, S.; Schulz, E.; Tranoy-Opalinski, I.; Vauzeilles, B.; Vayron, Ph.; Vergnes, L.; Vidal, S.; Wilmouth, S.

    2006-01-01

    What will organic chemistry do in the next forty years? This Perspective lists six tasks that have emerged during the first edition of ESYOP, a symposium devoted to the future of organic chemistry. The collective answer presented has been elaborated following a 4-step process: stimulating plenary lectures given by outstanding chemists and philosophers, short presentations given by each participant (average age: 34 years old), think-tank sessions and writing of the final report after the symposium. (authors)

  14. Taming sulfur dioxide: a breakthrough for its wide utilization in chemistry and biology.

    Science.gov (United States)

    Bisseret, Philippe; Blanchard, Nicolas

    2013-09-07

    Although sulfur dioxide (SO2) has been used as a reagent for organic chemistry for more than one hundred years, being endowed with quite a distinct and varied reactivity profile, which allows the synthesis of a large range of compounds, its notorious toxicity as well as its gaseous state have impeded its frequent utilization by chemists. We summarize recent studies in this emerging area aimed at stimulating its utilization in organic (including organometallic) chemistry thanks to the development of innocuous, bench-stable reliable SO2 donors. Proof-of-concept experiments have also been recently performed in biology with the design of organic SO2 donors having controlled release profiles under physiological conditions, either active against mycobacteria or used for clarifying the role of endogenously produced SO2 in living cells.

  15. Organic chemistry in a CO2 rich early Earth atmosphere

    Science.gov (United States)

    Fleury, Benjamin; Carrasco, Nathalie; Millan, Maëva; Vettier, Ludovic; Szopa, Cyril

    2017-12-01

    The emergence of life on the Earth has required a prior organic chemistry leading to the formation of prebiotic molecules. The origin and the evolution of the organic matter on the early Earth is not yet firmly understood. Several hypothesis, possibly complementary, are considered. They can be divided in two categories: endogenous and exogenous sources. In this work we investigate the contribution of a specific endogenous source: the organic chemistry occurring in the ionosphere of the early Earth where the significant VUV contribution of the young Sun involved an efficient formation of reactive species. We address the issue whether this chemistry can lead to the formation of complex organic compounds with CO2 as only source of carbon in an early atmosphere made of N2, CO2 and H2, by mimicking experimentally this type of chemistry using a low pressure plasma reactor. By analyzing the gaseous phase composition, we strictly identified the formation of H2O, NH3, N2O and C2N2. The formation of a solid organic phase is also observed, confirming the possibility to trigger organic chemistry in the upper atmosphere of the early Earth. The identification of Nitrogen-bearing chemical functions in the solid highlights the possibility for an efficient ionospheric chemistry to provide prebiotic material on the early Earth.

  16. Dynamic light scattering with applications to chemistry, biology, and physics

    CERN Document Server

    Berne, Bruce J

    2000-01-01

    Lasers play an increasingly important role in a variety of detection techniques, making inelastic light scattering a tool of growing value in the investigation of dynamic and structural problems in chemistry, biology, and physics. Until the initial publication of this work, however, no monograph treated the principles behind current developments in the field.This volume presents a comprehensive introduction to the principles underlying laser light scattering, focusing on the time dependence of fluctuations in fluid systems; it also serves as an introduction to the theory of time correlation f

  17. Adenine Synthesis in a Model Prebiotic Reaction: Connecting Origin of Life Chemistry with Biology.

    Science.gov (United States)

    Anumukonda, Lakshmi N; Young, Avery; Lynn, David G; Buckley, Ragan; Warrayat, Amena; Graves, Christina L; Bean, Heather D; Hud, Nicholas V

    2011-12-01

    Many high school laboratory experiments demonstrate concepts related to biological evolution, but few exist that allow students to investigate life's chemical origins. This series of laboratory experiments has been developed to allow students to explore and appreciate the deep connection that exists between prebiotic chemistry, chemical evolution, and contemporary biological systems. In the first experiment of the series, students synthesize adenine, one of the purine nucleobases of DNA and RNA, from plausibly prebiotic precursor molecules. Students compare their product to authentic standards using thin-layer chromatography. The second and third experiments of the series allow students to extract DNA from a familiar organism, the strawberry, and hydrolyze it, releasing adenine, which they can then compare to the previously chemically-synthesized adenine. A fourth, optional experiment is included where the technique of thin-layer chromatography is introduced and chromatographic skills are developed for use in the other three experiments that comprise this series. Concepts relating to organic and analytical chemistry, as well as biochemistry and DNA structure, are incorporated throughout, allowing this series of laboratory experiments to be easily inserted into existing laboratory courses and to reinforce concepts already included in any high school chemistry or biology curriculum.

  18. General Chemistry and Cellular and Molecular Biology: An Experiment in Curricular Symbiosis

    Science.gov (United States)

    Truman Schwartz, A.; Serie, Jan

    2001-11-01

    During the 1998-99 academic year, with the support of the Howard Hughes Medical Institute, we co-taught integrated courses in general chemistry and cell biology to 23 first-year students. The double course was organized around six units: I. Energetics: Harvesting (Bio)Chemical Energy; II. The Regulation of Biological Processes: Chemical Kinetics and Equilibrium; III. Membranes and Electrochemical Gradients; IV. Acids and Bases and the Regulation of pH; V. Intracellular Compartments and Transport; and VI. Cellular Communication. The chemistry and biology were both taught in a manner meant to enhance understanding of these major themes and to emphasize the relationships between the two disciplines. Both of us were present for all class sessions and shared teaching responsibilities. The examinations, which corresponded to the units, also stressed the interdependence of biology and chemistry. The laboratory components were not integrated; rather the students were dispersed among laboratory sections shared with students from more traditional lecture sections. The paper reports on this experiment in curricular symbiosis, which proved to be a challenging and rewarding learning experience for both the students and us.

  19. Recent Advances in the Chemistry and Biology of Podophyllotoxins.

    Science.gov (United States)

    Yu, Xiang; Che, Zhiping; Xu, Hui

    2017-04-03

    Podophyllotoxin and its related aryltetralin cyclolignans belong to a family of important products that exhibit various biological properties (e.g., cytotoxic, insecticidal, antifungal, antiviral, anti-inflammatory, neurotoxic, immunosuppressive, antirheumatic, antioxidative, antispasmogenic, and hypolipidemic activities). This Review provides a survey of podophyllotoxin and its analogues isolated from plants. In particular, recent developments in the elegant total chemical synthesis, structural modifications, biosynthesis, and biotransformation of podophyllotoxin and its analogues are summarized. Moreover, a deoxypodophyllotoxin-based chemosensor for selective detection of mercury ion is described. In addition to the most active podophyllotoxin derivatives in each series against human cancer cell lines and insect pests listed in the tables, the structure-activity relationships of podophyllotoxin derivatives as cytotoxic and insecticidal agents are also outlined. Future prospects and further developments in this area are covered at the end of the Review. We believe that this Review will provide necessary information for synthetic, medicinal, and pesticidal chemistry researchers who are interested in the chemistry and biology of podophyllotoxins. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Platensimycin and platencin: Inspirations for chemistry, biology, enzymology, and medicine.

    Science.gov (United States)

    Rudolf, Jeffrey D; Dong, Liao-Bin; Shen, Ben

    2017-06-01

    Natural products have served as the main source of drugs and drug leads, and natural products produced by microorganisms are one of the most prevalent sources of clinical antibiotics. Their unparalleled structural and chemical diversities provide a basis to investigate fundamental biological processes while providing access to a tremendous amount of chemical space. There is a pressing need for novel antibiotics with new mode of actions to combat the growing challenge of multidrug resistant pathogens. This review begins with the pioneering discovery and biological activities of platensimycin (PTM) and platencin (PTN), two antibacterial natural products isolated from Streptomyces platensis. The elucidation of their unique biochemical mode of action, structure-activity relationships, and pharmacokinetics is presented to highlight key aspects of their biological activities. It then presents an overview of how microbial genomics has impacted the field of PTM and PTN and revealed paradigm-shifting discoveries in terpenoid biosynthesis, fatty acid metabolism, and antibiotic and antidiabetic therapies. It concludes with a discussion covering the future perspectives of PTM and PTN in regard to natural products discovery, bacterial diterpenoid biosynthesis, and the pharmaceutical promise of PTM and PTN as antibiotics and for the treatment of metabolic disorders. PTM and PTN have inspired new discoveries in chemistry, biology, enzymology, and medicine and will undoubtedly continue to do so. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Roles of radiation chemistry in development and research of radiation biology

    International Nuclear Information System (INIS)

    Min Rui

    2009-01-01

    Radiation chemistry acts as a bridge connecting radiation physics with radiation biology in spatial and temporal insight. The theory, model, and methodology coming from radiation chemistry play an important role in the research and development of radiation biology. The chemical changes induced by ionizing radiation are involved not only in early event of biological effects caused by ionizing radiation but in function radiation biology, such as DNA damage and repair, sensitive modification, metabolism and function of active oxygen and so on. Following the research development of radiation biology, systems radiation biology, accurate quality and quantity of radiation biology effects need more methods and perfect tools from radiation chemistry. (authors)

  2. Organic chemistry in the atmosphere. [laboratory modeling of Titan atmosphere

    Science.gov (United States)

    Sagan, C.

    1974-01-01

    The existence of an at least moderately complex organic chemistry on Titan is stipulated based on clear evidence of methane, and at least presumptive evidence of hydrogen in its atmosphere. The ratio of methane to hydrogen is the highest of any atmosphere in the solar system. Irradiation of hydrogen/methane mixtures produces aromatic and aliphatic hydrocarbons. A very reasonable hypothesis assumes that the red cloud cover of Titan is made of organic chemicals. Two-carbon hydrocarbons experimentally produced from irradiated mixtures of methane, ammonia, water, and hydrogen bear out the possible organic chemistry of the Titanian environment.

  3. Misconception of pre-service chemistry teachers about the concept of resonances in organic chemistry course

    Science.gov (United States)

    Widarti, Hayuni Retno; Retnosari, Rini; Marfu'ah, Siti

    2017-08-01

    A descriptive quantitative research has been done to identify the level of understanding and misconceptions of the pre-service chemistry teachers related to the concept of resonance in the organic chemistry course. The subjects of the research were 51 students of State University of Malang, majoring Chemistry Education, currently in their fourth semester, 2015-2016 academic year who have taken the course of Organic Chemistry I. The instruments used in this research is a combination of 8 numbers of multiple choice tests with open answer questions and certainty of response index (CRI). The research findings revealed that there are still misconceptions found in the organic chemistry course, especially about the concept of resonance. There were several misconceptions of the pre-service chemistry teachers, such as resonance structures are in equilibrium with each other; resonance structures are two or more Lewis structures with different in arrangement of both atom and electron; resonance structures are only structures containing charged atoms; formal charge and resonance structures are not related; and the stability of resonance structures are only determined by location of charges in atoms found in such structures. There is also a lack of understanding of curved arrows notation to show electron pair movement.

  4. Using Popular Nonfiction in Organic Chemistry: Teaching More than Content

    Science.gov (United States)

    Amaral, Katie E.; Shibley, Ivan A., Jr.

    2010-01-01

    Assigning a popular nonfiction book as a supplemental text in organic chemistry can help students learn valuable skills. An analysis of student feedback on assignments related to a nonfiction book in two different organic courses revealed that students applied the information from the book, improved their communication skills, and were more…

  5. Building Bridges between Science Courses Using Honors Organic Chemistry Projects

    Science.gov (United States)

    Hickey, Timothy; Pontrello, Jason

    2016-01-01

    Introductory undergraduate science courses are traditionally offered as distinct units without formalized student interaction between classes. To bridge science courses, the authors used three Honors Organic Chemistry projects paired with other science courses. The honors students delivered presentations to mainstream organic course students and…

  6. Recent advances in the chemistry of organic thiocyanates.

    Science.gov (United States)

    Castanheiro, Thomas; Suffert, Jean; Donnard, Morgan; Gulea, Mihaela

    2016-02-07

    Organic thiocyanates are important synthetic intermediates to access valuable sulfur-containing compounds. In this review the different methods for their preparation and their synthetic applications will be presented. The literature of the last 15 years will be covered, highlighting selected recent advances in the chemistry of this class of compounds. We hope to offer chemists the tools to have a good grasp of this singular functionality and open the door to further progress in this chemistry.

  7. Organic chemistry on Titan: Surface interactions

    Science.gov (United States)

    Thompson, W. Reid; Sagan, Carl

    1992-01-01

    The interaction of Titan's organic sediments with the surface (solubility in nonpolar fluids) is discussed. How Titan's sediments can be exposed to an aqueous medium for short, but perhaps significant, periods of time is also discussed. Interactions with hydrocarbons and with volcanic magmas are considered. The alteration of Titan's organic sediments over geologic time by the impacts of meteorites and comets is discussed.

  8. The Organic Chemistry of Conducting Polymers

    Energy Technology Data Exchange (ETDEWEB)

    Tolbert, Laren Malcolm [Georgia Inst. of Technology, Atlanta, GA (United States)

    2014-12-01

    For the last several years, we have examined the fundamental principles of conduction in one-dimensional systems, i.e., molecular “wires”. It is, of course, widely recognized that such systems, as components of electronically conductive materials, function in a two- and three-dimensional milieu. Thus interchain hopping and grain-boundary resistivity are limiting conductivity factors in highly conductive materials, and overall conductivity is a function of through-chain and boundary hopping. We have given considerable attention to the basic principles underlying charge transport (the “rules of the game”) in two-dimensional systems by using model systems which allow direct observation of such processes, including the examination of tunneling and hopping as components of charge transfer. In related work, we have spent considerable effort on the chemistry of conjugated heteropolymers, most especially polythiophens, with the aim of using these most efficient of readily available electroactive polymers in photovoltaic devices.

  9. Organic chemistry. Strain-release amination.

    Science.gov (United States)

    Gianatassio, Ryan; Lopchuk, Justin M; Wang, Jie; Pan, Chung-Mao; Malins, Lara R; Prieto, Liher; Brandt, Thomas A; Collins, Michael R; Gallego, Gary M; Sach, Neal W; Spangler, Jillian E; Zhu, Huichin; Zhu, Jinjiang; Baran, Phil S

    2016-01-15

    To optimize drug candidates, modern medicinal chemists are increasingly turning to an unconventional structural motif: small, strained ring systems. However, the difficulty of introducing substituents such as bicyclo[1.1.1]pentanes, azetidines, or cyclobutanes often outweighs the challenge of synthesizing the parent scaffold itself. Thus, there is an urgent need for general methods to rapidly and directly append such groups onto core scaffolds. Here we report a general strategy to harness the embedded potential energy of effectively spring-loaded C-C and C-N bonds with the most oft-encountered nucleophiles in pharmaceutical chemistry, amines. Strain-release amination can diversify a range of substrates with a multitude of desirable bioisosteres at both the early and late stages of a synthesis. The technique has also been applied to peptide labeling and bioconjugation. Copyright © 2016, American Association for the Advancement of Science.

  10. Preface: Special Issue of the 5th International Symposium on Biological and Environmental Chemistry of DMS(P) and Related Compounds, Goa, India, 19–22 October 2010

    Digital Repository Service at National Institute of Oceanography (India)

    Stefels, J.; Shenoy, D.M.; Simo, R.; Malin, G.; Levasseur, M.; Belviso, S.; DileepKumar, M.

    This Special Issue of Biogeochemistry contains a selection of papers presented at the 5th International Symposium on Biological and Environmental Chemistry of DMS(P) and Related Compounds, organized at the National Institute of Oceanography (NIO...

  11. Advances in the Biology and Chemistry of Sialic Acids

    Science.gov (United States)

    Chen, Xi; Varki, Ajit

    2010-01-01

    Sialic acids are a subset of nonulosonic acids, which are nine-carbon alpha-keto aldonic acids. Natural existing sialic acid-containing structures are presented in different sialic acid forms, various sialyl linkages, and on diverse underlying glycans. They play important roles in biological, pathological, and immunological processes. Sialobiology has been a challenging and yet attractive research area. Recent advances in chemical and chemoenzymatic synthesis as well as large-scale E. coli cell-based production have provided a large library of sialoside standards and derivatives in amounts sufficient for structure-activity relationship studies. Sialoglycan microarrays provide an efficient platform for quick identification of preferred ligands for sialic acid-binding proteins. Future research on sialic acid will continue to be at the interface of chemistry and biology. Research efforts will not only lead to a better understanding of the biological and pathological importance of sialic acids and their diversity, but could also lead to the development of therapeutics. PMID:20020717

  12. Ethnobotany, chemistry, and biological activities of the genus Tithonia (Asteraceae).

    Science.gov (United States)

    Chagas-Paula, Daniela A; Oliveira, Rejane B; Rocha, Bruno A; Da Costa, Fernando B

    2012-02-01

    The genus Tithonia is an important source of diverse natural products, particularly sesquiterpene lactones, diterpenes, and flavonoids. The collected information in this review attempts to summarize the recent developments in the ethnobotany, biological activities, and secondary metabolite chemistry of this genus. More than 100 structures of natural products from Tithonia are reported in this review. The species that has been most investigated in this genus is T. diversifolia, from which ca. 150 compounds were isolated. Biological studies are described to evaluate the anti-inflammatory, analgesic, antimalarial, antiviral, antidiabetic, antidiarrhoeal, antimicrobial, antispasmodic, vasorelaxant, cancer-chemopreventive, cytotoxic, toxicological, bioinsecticide, and repellent activities. A few of these studies have been carried out with isolated compounds from Tithonia species, but the majority has been conducted with different extracts. The relationship between the biological activity and the toxicity of compounds isolated from the plants of this genus as well as T. diversifolia extracts still remains unclear, and mechanisms of action remain to be determined. Copyright © 2012 Verlag Helvetica Chimica Acta AG, Zürich.

  13. Synthetic biology and biomimetic chemistry as converging technologies fostering a new generation of smart biosensors.

    Science.gov (United States)

    Scognamiglio, Viviana; Antonacci, Amina; Lambreva, Maya D; Litescu, Simona C; Rea, Giuseppina

    2015-12-15

    Biosensors are powerful tunable systems able to switch between an ON/OFF status in response to an external stimulus. This extraordinary property could be engineered by adopting synthetic biology or biomimetic chemistry to obtain tailor-made biosensors having the desired requirements of robustness, sensitivity and detection range. Recent advances in both disciplines, in fact, allow to re-design the configuration of the sensing elements - either by modifying toggle switches and gene networks, or by producing synthetic entities mimicking key properties of natural molecules. The present review considered the role of synthetic biology in sustaining biosensor technology, reporting examples from the literature and reflecting on the features that make it a useful tool for designing and constructing engineered biological systems for sensing application. Besides, a section dedicated to bioinspired synthetic molecules as powerful tools to enhance biosensor potential is reported, and treated as an extension of the concept of biomimetic chemistry, where organic synthesis is used to generate artificial molecules that mimic natural molecules. Thus, the design of synthetic molecules, such as aptamers, biomimetics, molecular imprinting polymers, peptide nucleic acids, and ribozymes were encompassed as "products" of biomimetic chemistry. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Living GenoChemetics by hyphenating synthetic biology and synthetic chemistry in vivo.

    Science.gov (United States)

    Sharma, Sunil V; Tong, Xiaoxue; Pubill-Ulldemolins, Cristina; Cartmell, Christopher; Bogosyan, Emma J A; Rackham, Emma J; Marelli, Enrico; Hamed, Refaat B; Goss, Rebecca J M

    2017-08-09

    Marrying synthetic biology with synthetic chemistry provides a powerful approach toward natural product diversification, combining the best of both worlds: expediency and synthetic capability of biogenic pathways and chemical diversity enabled by organic synthesis. Biosynthetic pathway engineering can be employed to insert a chemically orthogonal tag into a complex natural scaffold affording the possibility of site-selective modification without employing protecting group strategies. Here we show that, by installing a sufficiently reactive handle (e.g., a C-Br bond) and developing compatible mild aqueous chemistries, synchronous biosynthesis of the tagged metabolite and its subsequent chemical modification in living culture can be achieved. This approach can potentially enable many new applications: for example, assay of directed evolution of enzymes catalyzing halo-metabolite biosynthesis in living cells or generating and following the fate of tagged metabolites and biomolecules in living systems. We report synthetic biological access to new-to-nature bromo-metabolites and the concomitant biorthogonal cross-coupling of halo-metabolites in living cultures.Coupling synthetic biology and chemical reactions in cells is a challenging task. The authors engineer bacteria capable of generating bromo-metabolites, develop a mild Suzuki-Miyaura cross-coupling reaction compatible with cell growth and carry out the cross-coupling chemistry in live cell cultures.

  15. Proceedings of the 17. Annual Meeting of the Brazilian Chemistry Society; 7. National Symposium on Inorganic Chemistry. Abstracts

    International Nuclear Information System (INIS)

    1994-01-01

    These 17. Annual Meeting of the Brazilian Chemistry Society and 7. National Symposium on Inorganic Chemistry present several subjects of different interests for the participants, including sections about inorganic chemistry; organic chemistry; environmental chemistry; technological chemistry; electrochemistry; physical chemistry; photochemistry; chemical education; natural products; analytical chemistry and biological chemistry. (C.G.C.)

  16. "Drug" Discovery with the Help of Organic Chemistry.

    Science.gov (United States)

    Itoh, Yukihiro; Suzuki, Takayoshi

    2017-01-01

    The first step in "drug" discovery is to find compounds binding to a potential drug target. In modern medicinal chemistry, the screening of a chemical library, structure-based drug design, and ligand-based drug design, or a combination of these methods, are generally used for identifying the desired compounds. However, they do not necessarily lead to success and there is no infallible method for drug discovery. Therefore, it is important to explore medicinal chemistry based on not only the conventional methods but also new ideas. So far, we have found various compounds as drug candidates. In these studies, some strategies based on organic chemistry have allowed us to find drug candidates, through 1) construction of a focused library using organic reactions and 2) rational design of enzyme inhibitors based on chemical reactions catalyzed by the target enzyme. Medicinal chemistry based on organic chemical reactions could be expected to supplement the conventional methods. In this review, we present drug discovery with the help of organic chemistry showing examples of our explorative studies on histone deacetylase inhibitors and lysine-specific demethylase 1 inhibitors.

  17. Micro-segmented flow applications in chemistry and biology

    CERN Document Server

    Cahill, Brian

    2014-01-01

    The book is dedicated to the method and application potential of micro segmented flow. The recent state of development of this powerful technique is presented in 12 chapters by leading researchers from different countries. In the first section, the principles of generation and manipulation of micro-fluidic segments are explained. In the second section, the micro continuous-flow synthesis of different types of nanomaterials is shown as a typical example for the use of advantages of the technique in chemistry. In the third part, the particular importance of the technique in biotechnical applications is presented demonstrating the progress for miniaturized cell-free processes, for molecular biology and DNA-based diagnostis and sequencing as well as for the development of antibiotics and the evaluation of toxic effects in medicine and environment.

  18. The Critical Role of Organic Chemistry in Drug Discovery.

    Science.gov (United States)

    Rotella, David P

    2016-10-19

    Small molecules remain the backbone for modern drug discovery. They are conceived and synthesized by medicinal chemists, many of whom were originally trained as organic chemists. Support from government and industry to provide training and personnel for continued development of this critical skill set has been declining for many years. This Viewpoint highlights the value of organic chemistry and organic medicinal chemists in the complex journey of drug discovery as a reminder that basic science support must be restored.

  19. Beyond prostaglandins - chemistry and biology of cyclic oxygenated metabolites formed by free-radical pathways from polyunsaturated fatty acids

    Czech Academy of Sciences Publication Activity Database

    Jahn, Ullrich; Galano, J. M.; Durand, T.

    2008-01-01

    Roč. 47, č. 32 (2008), s. 5894-5955 ISSN 1433-7851 Institutional research plan: CEZ:AV0Z40550506 Keywords : biological activity * fatty acids * isoprostanes * oxidation * total synthesis Subject RIV: CC - Organic Chemistry Impact factor: 10.879, year: 2008

  20. Water as Life, Death, and Power: Building an Integrated Interdisciplinary Course Combining Perspectives from Anthropology, Biology, and Chemistry

    Science.gov (United States)

    Willermet, Cathy; Mueller, Anja; Juris, Stephen J.; Drake, Eron; Upadhaya, Samik; Chhetri, Pratik

    2013-01-01

    In response to a request from a campus student organization, faculty from three fields came together to develop and teach an integrated interdisciplinary course on water issues and social activism. This course, "Water as Life, Death, and Power", brought together topics from the fields of anthropology, biology and chemistry to explore…

  1. Oxidation and Reduction Reactions in Organic Chemistry

    Science.gov (United States)

    Shibley, Ivan A., Jr.; Amaral, Katie E.; Aurentz, David J.; McCaully, Ronald J.

    2010-01-01

    A variety of approaches to the concept of oxidation and reduction appear in organic textbooks. The method proposed here is different than most published approaches. The oxidation state is calculated by totaling the number of heterogeneous atoms, [pi]-bonds, and rings. A comparison of the oxidation states of reactant and product determine what type…

  2. Learning Organic Chemistry Through Natural Products

    Indian Academy of Sciences (India)

    However, geraniol lacks an important feature present in many organic compounds, in general, and in natural products, in particular. The molecular structure of geraniol is superimposable on its mirror image and hence it is achiral. The problem of structure determination has an added dimension in molecules which are chiral.

  3. Isoprostanes, neuroprostanes and phytoprostanes: An overview of 25years of research in chemistry and biology.

    Science.gov (United States)

    Galano, Jean-Marie; Lee, Yiu Yiu; Oger, Camille; Vigor, Claire; Vercauteren, Joseph; Durand, Thierry; Giera, Martin; Lee, Jetty Chung-Yung

    2017-10-01

    Since the beginning of the 1990's diverse types of metabolites originating from polyunsaturated fatty acids, formed under autooxidative conditions were discovered. Known as prostaglandin isomers (or isoprostanoids) originating from arachidonic acid, neuroprostanes from docosahexaenoic acid, and phytoprostanes from α-linolenic acid proved to be prevalent in biology. The syntheses of these compounds by organic chemists and the development of sophisticated mass spectrometry methods has boosted our understanding of the isoprostanoid biology. In recent years, it has become accepted that these molecules not only serve as markers of oxidative damage but also exhibit a wide range of bioactivities. In addition, isoprostanoids have emerged as indicators of oxidative stress in humans and their environment. This review explores in detail the isoprostanoid chemistry and biology that has been achieved in the past three decades. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Applications of the Cambridge Structural Database in organic chemistry and crystal chemistry.

    Science.gov (United States)

    Allen, Frank H; Motherwell, W D Samuel

    2002-06-01

    The Cambridge Structural Database (CSD) and its associated software systems have formed the basis for more than 800 research applications in structural chemistry, crystallography and the life sciences. Relevant references, dating from the mid-1970s, and brief synopses of these papers are collected in a database, DBUse, which is freely available via the CCDC website. This database has been used to review research applications of the CSD in organic chemistry, including supramolecular applications, and in organic crystal chemistry. The review concentrates on applications that have been published since 1990 and covers a wide range of topics, including structure correlation, conformational analysis, hydrogen bonding and other intermolecular interactions, studies of crystal packing, extended structural motifs, crystal engineering and polymorphism, and crystal structure prediction. Applications of CSD information in studies of crystal structure precision, the determination of crystal structures from powder diffraction data, together with applications in chemical informatics, are also discussed.

  5. Piaget and Organic Chemistry: Teaching Introductory Organic Chemistry through Learning Cycles

    Science.gov (United States)

    Libby, R. Daniel

    1995-07-01

    This paper describes the first application of the Piaget-based learning cycle technique (Atkin & Karplus, Sci. Teach. 1962, 29, 45-51) to an introductory organic chemistry course. It also presents the step-by-step process used to convert a lecture course into a discussion-based active learning course. The course is taught in a series of learning cycles. A learning cycle is a three phase process that provides opportunities for students to explore new material and work with an instructor to recognize logical patterns in data, and devise and test hypotheses. In this application, the first phase, exploration, involves out-of-class student evaluation of data in attempts to identify significant trends and develop hypotheses that might explain the trends in terms of fundamental scientific principles. In the second phase, concept invention, the students and instructor work together in-class to evaluate student hypotheses and find concepts that work best in explaining the data. The third phase, application, is an out-of-class application of the concept to new situations. The development of learning cycles from lecture notes is presented as an 8 step procedure. The process involves revaluation and restructuring of the course material to maintain a continuity of concept development according to the instructor's logic, dividing topics into individual concepts or techniques, and refocusing the presentation in terms of large numbers of examples that can serve as data for students in their exploration and application activities. A sample learning cycle and suggestions for ways of limited implementation of learning cycles into existing courses are also provided.

  6. Academia–Industry Symbiosis in Organic Chemistry

    Science.gov (United States)

    2015-01-01

    Conspectus Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial “sponsoring” is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry’s point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry’s desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply “pure science” research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the “real world” at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate

  7. Academia-industry symbiosis in organic chemistry.

    Science.gov (United States)

    Michaudel, Quentin; Ishihara, Yoshihiro; Baran, Phil S

    2015-03-17

    Collaboration between academia and industry is a growing phenomenon within the chemistry community. These sectors have long held strong ties since academia traditionally trains the future scientists of the corporate world, but the recent drastic decrease of public funding is motivating the academic world to seek more private grants. This concept of industrial "sponsoring" is not new, and in the past, some companies granted substantial amounts of money per annum to various academic institutions in exchange for prime access to all their scientific discoveries and inventions. However, academic and industrial interests were not always aligned, and therefore the investment has become increasingly difficult to justify from industry's point of view. With fluctuating macroeconomic factors, this type of unrestricted grant has become more rare and has been largely replaced by smaller and more focused partnerships. In our view, forging a partnership with industry can be a golden opportunity for both parties and can represent a true symbiosis. This type of project-specific collaboration is engendered by industry's desire to access very specific academic expertise that is required for the development of new technologies at the forefront of science. Since financial pressures do not allow companies to spend the time to acquire this expertise and even less to explore fundamental research, partnering with an academic laboratory whose research is related to the problem gives them a viable alternative. From an academic standpoint, it represents the perfect occasion to apply "pure science" research concepts to solve problems that benefit humanity. Moreover, it offers a unique opportunity for students to face challenges from the "real world" at an early stage of their career. Although not every problem in industry can be solved by research developments in academia, we argue that there is significant scientific overlap between these two seemingly disparate groups, thereby presenting an

  8. Alternative Conceptions of Organic Chemistry Topics among Fourth Year Chemistry Students

    Science.gov (United States)

    Rushton, Gregory T.; Hardy, Rebecca C.; Gwaltney, Kevin P.; Lewis, Scott E.

    2008-01-01

    This study describes the conceptual understanding for a series of fundamental organic concepts by fourth year chemistry students from a midsize, southeastern, state university. Student volunteers (n = 19) participated in semi-structured interviews using a think aloud protocol. The interview questions were eleven multiple choice questions selected…

  9. Medical Mycology and the Chemistry Classroom: Germinating Student Interest in Organic Chemistry

    Science.gov (United States)

    Bliss, Joseph M.; Reid, Christopher W.

    2013-01-01

    Efforts to provide active research context to introductory courses in basic sciences are likely to better engage learners and provide a framework for relevant concepts. A simple teaching and learning experiment was conducted to use concepts in organic chemistry to solve problems in the life sciences. Bryant University is a liberal arts university…

  10. Implementing a Student-Designed Green Chemistry Laboratory Project in Organic Chemistry

    Science.gov (United States)

    Graham, Kate J.; Jones, T. Nicholas; Schaller, Chris P.; McIntee, Edward J.

    2014-01-01

    A multiweek organic chemistry laboratory project is described that emphasizes sustainable practices in experimental design. An emphasis on student-driven development of the project is meant to mirror the independent nature of research. Students propose environmentally friendly modifications of several reactions. With instructor feedback, students…

  11. Extraterrestrial organic chemistry: from the interstellar medium to the origins of life. Part 2: complex organic chemistry in the environment of planets and satellites.

    Science.gov (United States)

    Raulin, F; Kobayashi, K

    2001-01-01

    During COSPAR'00 in Warsaw, Poland, in the frame of Sub-Commission F.3 events (Planetary Biology and Origins of Life), part of COSPAR Commission F (Life Sciences as Related to Space), and Commission B events (Space Studies of the Earth-Moon System, Planets, and Small Bodies of the Solar System) a large joint symposium (F.3.4/B0.8) was held on extraterrestrial organic chemistry. Part 2 of this symposium was devoted to complex organic chemistry in the environment of planets and satellites. The aim of this event was to cover and review new data which have been recently obtained and to give new insights on data which are expected in the near future to increase our knowledge of the complex organic chemistry occurring in several planets and satellites of the Solar System, outside the earth, and their implications for exobiology and life in the universe. The event was composed of two main parts. The first part was mainly devoted to the inner planets and Europa and the search for signatures of life or organics in those environments. The second part was related to the study of the outer solar system.

  12. Gender and students' interests in organic chemistry topics at the ...

    African Journals Online (AJOL)

    The study is a reflection on the processes of the teaching and learning of science with special attention on gender influence in students' interests in learning organic chemistry in Senior Secondary Schools. Gender studies is gaining wide research attention today and there is increased awareness of activities for eradicating ...

  13. The 2010 Chemistry Nobel Prize: Pd (0)-Catalyzed Organic Synthesis

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 2. The 2010 Chemistry Nobel Prize: Pd(O)-Catalyzed Organic Synthesis. Gopalpur Nagendrappa Y C Sunil Kumar. General Article Volume 16 Issue 2 February 2011 pp 152-164 ...

  14. Green chemistry principles in organic compound synthesis and analysis

    Directory of Open Access Journals (Sweden)

    Ruchi Verma

    2014-03-01

    Full Text Available The present review focus on various green chemistry approaches which could be utilized in the organic compounds in practical classes for undergraduate level in comparison of conventional methods. These methods avoid the usage of hazardous substances and are environmental friendly.

  15. Biobased Organic Chemistry Laboratories as Sustainable Experiment Alternatives

    Science.gov (United States)

    Silverman, Julian R.

    2016-01-01

    As nonrenewable resources deplete and educators seek relevant interdisciplinary content for organic chemistry instruction, biobased laboratory experiments present themselves as potential alternatives to petroleum-based transformations, which offer themselves as sustainable variations on important themes. Following the principles of green chemistry…

  16. Synthesis and Chemistry of Organic Geminal Di- and Triazides.

    Science.gov (United States)

    Häring, Andreas P; Kirsch, Stefan F

    2015-11-06

    This review recapitulates all available literature dealing with the synthesis and reactivity of geminal organic di- and triazides. These compound classes are, to a large extent, unexplored despite their promising chemical properties and their simple preparation. In addition, the chemistry of carbonyl diazide (2) and tetraazidomethane (105) is described in separate sections.

  17. Does Mechanistic Thinking Improve Student Success in Organic Chemistry?

    Science.gov (United States)

    Grove, Nathaniel P.; Cooper, Melanie M.; Cox, Elizabeth L.

    2012-01-01

    The use of the curved-arrow notation to depict electron flow during mechanistic processes is one of the most important representational conventions in the organic chemistry curriculum. Our previous research documented a disturbing trend: when asked to predict the products of a series of reactions, many students do not spontaneously engage in…

  18. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment

    Science.gov (United States)

    Bucholtz, Ehren C.

    2007-01-01

    A new lab esterification reaction based on biodiesel preparation and viscosity, which provides a model experience of industrial process to understand oxidation of vicinal alcohols by periodic acid, is presented. This new desertification experiment and periodate analysis of glycerol for the introductory organic chemistry laboratory provides an…

  19. Biodiesel from Seeds: An Experiment for Organic Chemistry

    Science.gov (United States)

    Goldstein, Steven W.

    2014-01-01

    Plants can store the chemical energy required by their developing offspring in the form of triglycerides. These lipids can be isolated from seeds and then converted into biodiesel through a transesterification reaction. This second-year undergraduate organic chemistry laboratory experiment exemplifies the conversion of an agricultural energy…

  20. Sudoku Puzzles for First-Year Organic Chemistry Students

    Science.gov (United States)

    Perez, Alice L.; Lamoureux, G.

    2007-01-01

    Sudoku puzzle was designed to teach about amino acids and functional groups to the students of undergraduate organic chemistry students. The puzzles focus on helping the student learn the name, 3-letter code and 1-letter code of common amino acids and functional groups.

  1. Concept of Green Chemistry-Redesigning Organic Synthesis

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 13; Issue 11. Concept of Green Chemistry - Redesigning Organic Synthesis. Bharati V Badami. General Article Volume 13 Issue 11 November 2008 pp 1041-1048. Fulltext. Click here to view fulltext PDF. Permanent link:

  2. Promoting Representational Competence with Molecular Models in Organic Chemistry

    Science.gov (United States)

    Stull, Andrew T.; Gainer, Morgan; Padalkar, Shamin; Hegarty, Mary

    2016-01-01

    Mastering the many different diagrammatic representations of molecules used in organic chemistry is challenging for students. This article summarizes recent research showing that manipulating 3-D molecular models can facilitate the understanding and use of these representations. Results indicate that students are more successful in translating…

  3. A Simple Mnemonic for Tautomerization Mechanisms in Organic Chemistry

    Science.gov (United States)

    Stephens, Chad E.

    2010-01-01

    The familiar word OREO (as in the cookie) is presented as a simple mnemonic for remembering the basic steps of the classical tautomerization mechanisms in organic chemistry. For acid-catalyzed tautomerizations, OREO stands for proton on, resonance, proton off. For base-catalyzed tautomerizations, OREO stands for proton off, resonance, proton on.…

  4. Integrating Symmetry in Stereochemical Analysis in Introductory Organic Chemistry

    Science.gov (United States)

    Taagepera, Mare; Arasasingham, Ramesh D.; King, Susan; Potter, Frank; Martorell, Ingrid; Ford, David; Wu, Jason; Kearney, Aaron M.

    2011-01-01

    We report a comparative study using "knowledge space theory" (KAT) to assess the impact of a hands-on laboratory exercise that used molecular model kits to emphasize the connections between a plane of symmetry, Charity, and isomerism in an introductory organic chemistry course. The experimental design compared three groups of…

  5. Application and Utilization of Electrochemistry in Organic Chemistry

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš

    2011-01-01

    Roč. 15, č. 17 (2011), s. 2921-2922 ISSN 1385-2728 R&D Projects: GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40400503 Keywords : electrochemistry * organic chemistry * applications Subject RIV: CG - Electrochemistry Impact factor: 3.064, year: 2011

  6. Analyzing Students' Understanding of Models and Modeling Referring to the Disciplines Biology, Chemistry, and Physics

    Science.gov (United States)

    Krell, Moritz; Reinisch, Bianca; Krüger, Dirk

    2015-01-01

    In this study, secondary school students' (N?=?617; grades 7 to 10) understanding of models and modeling was assessed using tasks which explicitly refer to the scientific disciplines of biology, chemistry, and physics and, as a control, to no scientific discipline. The students' responses are interpreted as their biology-, chemistry-, and…

  7. Alcohol Pharmacology Education Partnership: Using Chemistry and Biology Concepts to Educate High School Students about Alcohol

    Science.gov (United States)

    Godin, Elizabeth A.; Kwiek, Nicole; Sikes, Suzanne S.; Halpin, Myra J.; Weinbaum, Carolyn A.; Burgette, Lane F.; Reiter, Jerome P.; Schwartz-Bloom, Rochelle D.

    2014-01-01

    We developed the Alcohol Pharmacology Education Partnership (APEP), a set of modules designed to integrate a topic of interest (alcohol) with concepts in chemistry and biology for high school students. Chemistry and biology teachers (n = 156) were recruited nationally to field-test APEP in a controlled study. Teachers obtained professional…

  8. 8. International Conference on Pulse Investigations in Chemistry, Biology and Physics - PULS'2008. Abstracts

    International Nuclear Information System (INIS)

    2008-01-01

    The Report comprises abstracts of 68 communications (oral and posters) presented during the 8. International Conference on Pulse Investigations in Chemistry, Biology and Physics - PULS'2008, held on September 6 - 12, 2008 in Cracow. Presentations cover a variety of research fields representing different fields of pulse radiolysis in chemistry, biology and physics

  9. Students’ experienced coherence between chemistry and biology in context-based secondary science education

    NARCIS (Netherlands)

    Boer, H.J.; Prins, Gjalt; Goedhart, M.J.; Boersma, Kerst

    2014-01-01

    In current biology and chemistry secondary school practice, coherence between the subjects chemistry and biology is underexposed or even ignored. This is incongruent with the current scientific practice, in which the emphasis is shifting towards inter- and multidisciplinarity. These problems have

  10. Matrices for Sensors from Inorganic, Organic, and Biological Nanocomposites

    Directory of Open Access Journals (Sweden)

    Eugenia Pechkova

    2011-08-01

    Full Text Available Matrices and sensors resulting from inorganic, organic and biological nanocomposites are presented in this overview. The term nanocomposite designates a solid combination of a matrix and of nanodimensional phases differing in properties from the matrix due to dissimilarities in structure and chemistry. The nanoocomposites chosen for a wide variety of health and environment sensors consist of Anodic Porous Allumina and P450scc, Carbon nanotubes and Conductive Polymers, Langmuir Blodgett Films of Lipases, Laccases, Cytochromes and Rhodopsins, Three-dimensional Nanoporous Materials and Nucleic Acid Programmable Protein Arrays.

  11. Biomaterials — where biology, physics, chemistry, engineering and medicine meet

    Science.gov (United States)

    Hing, K. A.

    2008-03-01

    The success or failure of an implant material in the body depends on a complex interaction between a synthetic 'foreign body' and the 'host tissue'. These interactions occur at many levels from the sub-microscopic level, where subtle changes in the surface physio-chemistry can substantially alter the nature of the biomaterial-host tissue interface, through the microscopical level (e.g. sensitivity to surface topography) to the macrostructural level (e.g. dependence on scaffold porosity). Thus the factors that control these responses are not only biologically determined but also mechanically, physically and chemically mediated, although identifying where one starts and the other finishes can be difficult. Design of a successful medical device has therefore to call on expertise within a wide range of disciplines. In terms of both investigating the basic science behind the factors which orchestrate a biological response and developing research tools that enable study of these responses. However, a medical device must also meet the economic and practical demands of health care professionals who will ultimately be using it in the clinic. Bone graft substitute materials are used in orthopaedics as an alternative or adjunct to autografting, a practice where the patient 'donates' bone from a healthy site to aid bone repair at a damaged or diseased site. These materials are used in a wide range of procedures from total hip revision to spinal fusion and their evolution over the last 10 years illustrates how an interdisciplinary approach has benefited their development and may lead to further innovation in the future.

  12. Progress in organic and physical chemistry structures and mechanisms

    CERN Document Server

    Zaikov, Gennady E; Lobanov, Anton V

    2013-01-01

    Progress in Organic and Physical Chemistry: Structures and Mechanisms provides a collection of new research in the field of organic and physical properties, including new research on: The physical principles of the conductivity of electrical conducting polymer compounds The dependence on constants of electromagnetic interactions upon electron spacial-energy characteristics Effects of chitosan molecultural weight on rehological behavior of chitosan modified nanoclay at hight hydrated state Bio-structural energy criteria of functional states in normal and pathological conditions Potentiometric study on the international between devalent cations and sodium carboxylates in aqueous solutions Structural characteristic changes in erythrocyte membranes of mice bearing Alzheimer's-like disease caused by the olfactory bulbetomy This volume is intended to provide an overview of new studies and research for engineers, faculty, researchers, and upper-level students in the field of organic and physical chemistry.

  13. Students' Energy Understanding Across Biology, Chemistry, and Physics Contexts

    Science.gov (United States)

    Opitz, S. T.; Neumann, K.; Bernholt, S.; Harms, U.

    2017-07-01

    Energy is considered both as a disciplinary core idea and as a concept cutting across science disciplines. Most previous approaches studied progressing energy understanding in specific disciplinary contexts, while disregarding the relation of understanding across them. Hence, this study provides a systematic analysis of cross-disciplinary energy learning. On the basis of a cross-sectional study with n = 742 students from grades 6, 8, and 10, we analyze students' progression in understanding energy across biology, chemistry, and physics contexts. The study is guided by three hypothetical scenarios that describe how the connection between energy understanding in the three disciplinary contexts changes across grade levels. These scenarios are compared using confirmatory factor analysis (CFA). The results suggest that, from grade 6 to grade 10, energy understanding in the three disciplinary contexts is highly interrelated, thus indicating a parallel progression of energy understanding in the three disciplinary contexts. In our study, students from grade 6 onwards appeared to have few problems to apply one energy understanding across the three disciplinary contexts. These findings were unexpected, as previous research concluded that students likely face difficulties in connecting energy learning across disciplinary boundaries. Potential reasons for these results and the characteristics of the observed cross-disciplinary energy understanding are discussed in the light of earlier findings and implications for future research, and the teaching of energy as a core idea and a crosscutting concept are addressed.

  14. Synthesis at the interface of chemistry and biology.

    Science.gov (United States)

    Wu, Xu; Schultz, Peter G

    2009-09-09

    As the focus of synthesis increasingly shifts from its historical emphasis on molecular structure to function, improved strategies are clearly required for the generation of molecules with defined physical, chemical, and biological properties. In contrast, living organisms are remarkably adept at producing molecules and molecular assemblies with an impressive array of functions - from enzymes and antibodies to the photosynthetic center. Thus, the marriage of Nature's synthetic strategies, molecules, and biosynthetic machinery with more traditional synthetic approaches might enable the generation of molecules with properties difficult to achieve by chemical strategies alone. Here we illustrate the potential of this approach and overview some opportunities and challenges in the coming years.

  15. Topological data analysis: A promising big data exploration tool in biology, analytical chemistry and physical chemistry.

    Science.gov (United States)

    Offroy, Marc; Duponchel, Ludovic

    2016-03-03

    An important feature of experimental science is that data of various kinds is being produced at an unprecedented rate. This is mainly due to the development of new instrumental concepts and experimental methodologies. It is also clear that the nature of acquired data is significantly different. Indeed in every areas of science, data take the form of always bigger tables, where all but a few of the columns (i.e. variables) turn out to be irrelevant to the questions of interest, and further that we do not necessary know which coordinates are the interesting ones. Big data in our lab of biology, analytical chemistry or physical chemistry is a future that might be closer than any of us suppose. It is in this sense that new tools have to be developed in order to explore and valorize such data sets. Topological data analysis (TDA) is one of these. It was developed recently by topologists who discovered that topological concept could be useful for data analysis. The main objective of this paper is to answer the question why topology is well suited for the analysis of big data set in many areas and even more efficient than conventional data analysis methods. Raman analysis of single bacteria should be providing a good opportunity to demonstrate the potential of TDA for the exploration of various spectroscopic data sets considering different experimental conditions (with high noise level, with/without spectral preprocessing, with wavelength shift, with different spectral resolution, with missing data). Copyright © 2016 Elsevier B.V. All rights reserved.

  16. 2-Aminothiophene scaffolds: Diverse biological and pharmacological attributes in medicinal chemistry.

    Science.gov (United States)

    Bozorov, Khurshed; Nie, Li Fei; Zhao, Jiangyu; Aisa, Haji A

    2017-11-10

    2-Aminothiophenes are important five-membered heterocyclic building blocks in organic synthesis, and the chemistry of these small molecules is still developing based on the discovery of cyclization by Gewald. Another attractive feature of 2-aminothiophene scaffolds is their ability to act as synthons for the synthesis of biological active thiophene-containing heterocycles, conjugates and hybrids. Currently, the biological actions of 2-aminothiophenes or their 2-N-substituted analogues are still being investigated because of their various mechanisms of action (e.g., pharmacophore and pharmacokinetic properties). Likewise, the 2-aminothiophene family is used as diverse promising selective inhibitors, receptors, and modulators in medicinal chemistry, and these compounds even exhibit effective pharmacological properties in the various clinical phases of appropriate diseases. In this review, major biological and pharmacological reports on 2-aminothiophenes and related compounds have been highlighted; most perspective drug-candidate hits were selected for discussion and described, along with additional synthetic pathways. In addition, we focused on the literature dedicated to 2-aminothiophenes and 2-N-substituted derivatives, which have been published from 2010 to 2017. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. Infusing the Chemistry Curriculum with Green Chemistry Using Real-World Examples, Web Modules, and Atom Economy in Organic Chemistry Courses

    Science.gov (United States)

    Cann, Michael C.; Dickneider, Trudy A.

    2004-01-01

    Green chemistry is the awareness of the damaging environmental effects due to chemical research and inventions. There is emphasis on a need to include green chemistry in synthesis with atom economy in organic chemistry curriculum to ensure an environmentally conscious future generation of chemists, policy makers, health professionals and business…

  18. Biological regulation of atmospheric chemistry en route to planetary oxygenation.

    Science.gov (United States)

    Izon, Gareth; Zerkle, Aubrey L; Williford, Kenneth H; Farquhar, James; Poulton, Simon W; Claire, Mark W

    2017-03-28

    Emerging evidence suggests that atmospheric oxygen may have varied before rising irreversibly ∼2.4 billion years ago, during the Great Oxidation Event (GOE). Significantly, however, pre-GOE atmospheric aberrations toward more reducing conditions-featuring a methane-derived organic-haze-have recently been suggested, yet their occurrence, causes, and significance remain underexplored. To examine the role of haze formation in Earth's history, we targeted an episode of inferred haze development. Our redox-controlled (Fe-speciation) carbon- and sulfur-isotope record reveals sustained systematic stratigraphic covariance, precluding nonatmospheric explanations. Photochemical models corroborate this inference, showing Δ 36 S/Δ 33 S ratios are sensitive to the presence of haze. Exploiting existing age constraints, we estimate that organic haze developed rapidly, stabilizing within ∼0.3 ± 0.1 million years (Myr), and persisted for upward of ∼1.4 ± 0.4 Myr. Given these temporal constraints, and the elevated atmospheric CO 2 concentrations in the Archean, the sustained methane fluxes necessary for haze formation can only be reconciled with a biological source. Correlative δ 13 C Org and total organic carbon measurements support the interpretation that atmospheric haze was a transient response of the biosphere to increased nutrient availability, with methane fluxes controlled by the relative availability of organic carbon and sulfate. Elevated atmospheric methane concentrations during haze episodes would have expedited planetary hydrogen loss, with a single episode of haze development providing up to 2.6-18 × 10 18 moles of O 2 equivalents to the Earth system. Our findings suggest the Neoarchean likely represented a unique state of the Earth system where haze development played a pivotal role in planetary oxidation, hastening the contingent biological innovations that followed.

  19. The Impact of Nanoparticle Surface Chemistry on Biological Systems

    Science.gov (United States)

    Thorn, Angie Sue Morris

    The unique properties of nanomaterials, such as their small size and large surface area-to-volume ratios, have attracted tremendous interest in the scientific community over the last few decades. Thus, the synthesis and characterization of many different types of nanoparticles has been well defined and reported on in the literature. Current research efforts have redirected from the basic study of nanomaterial synthesis and their properties to more application-based studies where the development of functionally active materials is necessary. Today such nanoparticle-based systems exist for a range of biomedical applications including imaging, drug delivery and sensors. The inherent properties of the nanomaterial, although important, aren't always ideal for specific applications. In order to optimize nanoparticles for biomedical applications it is often desirable to tune their surface properties. Researchers have shown that these surface properties (such as charge, hydrophobicity, or reactivity) play a direct role in the interactions between nanoparticles and biological systems can be altered by attaching molecules to the surface of nanoparticles. In this work, the effects of physicochemical properties of a wide variety of nanoparticles was investigated using in vitro and in vivo models. For example, copper oxide (CuO) nanoparticles were of interest due to their instability in biological media. These nanoparticles undergo dissolution when in an aqueous environment and tend to aggregate. Therefore, the cytotoxicity of two sizes of CuO NPs was evaluated in cultured cells to develop a better understanding of how these propertied effect toxicity outcomes in biological systems. From these studies, it was determined that CuO NPs are cytotoxic to lung cells in a size-dependent manner and that dissolved copper ions contribute to the cytotoxicity however it is not solely responsible for cell death. Moreover, silica nanoparticles are one of the most commonly used nanomaterials

  20. Review and needs in actinide chemistry in relation with biological purposes

    Energy Technology Data Exchange (ETDEWEB)

    Ansoborlo, E.; Moulin, V.; Bion, L.; Doizi, D.; Moulin, C.; Cote, G.; Madic, C.; Van der Lee, J

    2004-07-01

    In case of accidental release of radionuclides in the environment, actinides could occur and may present an healthy risk for human beings. In order to study their behavior in human organism (metabolism, retention, excretion), it is of prime importance to know solution actinide chemistry, and more particularly thermodynamic constants, which will allow to determine their speciation: speciation governs biological availability and toxicity of elements and is also of great interest for decorporation purposes. In this framework, a CEA working group on speciation has been created in order to share data both on thermodynamic constants and on speciation analytical methods, interesting chemists, environmentalists and biologists. It has been focused, in a first time, on actinides. The purpose of this paper is to present the state of the art on actinide speciation within biological media and to focus on the lack of information in order to orientate future research. (authors)

  1. Tc Chemistry in HLW: Role of Organic Complexants

    International Nuclear Information System (INIS)

    Hess, Nancy S.; Conradsen, Steven D.

    2003-01-01

    Tc complexation with organic compounds in tank waste plays a significant role in the redox chemistry of Tc and the partitioning of Tc between the supernatant and sludge components in waste tanks. These processes need to be understood so that strategies to effectively remove Tc from high-level nuclear waste prior to waste immobilization can be developed and so that long-term consequences of Tc remaining in residual waste after sludge removal can be evaluated. Only limited data on the stability of Tc-organic complexes exists and even less thermodynamic data on which to develop predictive models of Tc chemical behavior is available. To meet these challenges we are conducting a research program to study to develop thermodynamic data on Tc-organic complexation over a wide range of chemical conditions. We will attempt to characterize Tc-speciation in actual tank waste using state-of-the-art analytical organic chemistry, separations, and speciation techniques to validate our model. On the basis of such studies we will develop credible model of Tc chemistry in HLW that will allow prediction of Tc speciation in tank waste and Tc behavior during waste pretreatment processing and in waste tank residuals

  2. Environmental chemistry. Seventh edition

    Energy Technology Data Exchange (ETDEWEB)

    Manahan, S.E. [Univ. of Missouri, Columbia, MO (United States)

    1999-11-01

    This book presents a basic understanding of environmental chemistry and its applications. In addition to providing updated materials in this field, the book emphasizes the major concepts essential to the practice of environmental chemistry. Topics of discussion include the following: toxicological chemistry; toxicological chemistry of chemical substances; chemical analysis of water and wastewater; chemical analysis of wastes and solids; air and gas analysis; chemical analysis of biological materials and xenobiotics; fundamentals of chemistry; and fundamentals of organic chemistry.

  3. Advances in metabolome information retrieval: turning chemistry into biology. Part I: analytical chemistry of the metabolome.

    Science.gov (United States)

    Tebani, Abdellah; Afonso, Carlos; Bekri, Soumeya

    2017-08-24

    Metabolites are small molecules produced by enzymatic reactions in a given organism. Metabolomics or metabolic phenotyping is a well-established omics aimed at comprehensively assessing metabolites in biological systems. These comprehensive analyses use analytical platforms, mainly nuclear magnetic resonance spectroscopy and mass spectrometry, along with associated separation methods to gather qualitative and quantitative data. Metabolomics holistically evaluates biological systems in an unbiased, data-driven approach that may ultimately support generation of hypotheses. The approach inherently allows the molecular characterization of a biological sample with regard to both internal (genetics) and environmental (exosome, microbiome) influences. Metabolomics workflows are based on whether the investigator knows a priori what kind of metabolites to assess. Thus, a targeted metabolomics approach is defined as a quantitative analysis (absolute concentrations are determined) or a semiquantitative analysis (relative intensities are determined) of a set of metabolites that are possibly linked to common chemical classes or a selected metabolic pathway. An untargeted metabolomics approach is a semiquantitative analysis of the largest possible number of metabolites contained in a biological sample. This is part I of a review intending to give an overview of the state of the art of major metabolic phenotyping technologies. Furthermore, their inherent analytical advantages and limits regarding experimental design, sample handling, standardization and workflow challenges are discussed.

  4. The Gravity of Regenerative Medicine; Physics, Chemistry & Biology behind it

    Directory of Open Access Journals (Sweden)

    Dedeepiya V

    2008-01-01

    Full Text Available The in-vitro expansion of cells of the organs/tissues and their re-implantation into the affected region/ tissue for treating cell/organ failure have been in practice for long, but in limited specialties. The in-vitro cell culture protocols use variety of biological reagents derived from animal sources and recombinant technologies. However, the optimal quantity of such biological components such as growth factors, cytokines etc.,needed for such cells to be grown in a non-physiological environment is still unknown. The use of such biological components have started to stir a controversy of late, due to the recognition of its potential hazards such as spread of prion diseases and contamination with non-human sialic acid proteins. Therefore synthetic reproducible biomaterials are gaining popularity in cell culture and tissue engineering. The biomaterials made of several chemical components based on physical parameters are starting to change certain concepts about the niche of cell culture and that of stem cell expansion and differentiation to specific lineages. Engler et al have already proven that a simple change in the matrix elasticity alone could change the lineage of the cells. Spencer et al have reported that a change in bioelectricity could change the morphogenesis during development. NCRM has been involved in cell culture and tissue engineering using approximately 240 different materials ranging from polymer hydrogel, gel with adherent inserts, nano composite materials, nano-coating technologies, nano-sheets and nano-films. These materials are used in cell culture in different hybrid combinations such as Floating 3D cell culture without adherent components in a homogenous hydrogel. Floating 3D cell culture with anchorage inserts. Flat surface- 2D adherent cell culture. Combined flat surface 2D cell culture (for differentiating cells and floating 3D culture (for undifferentiated cells. These combinations have started yielding several

  5. A Forty Year Odyssey in Metallo-Organic Chemistry.

    Science.gov (United States)

    Nicholas, Kenneth M

    2015-07-17

    In this invited Perspective, I provide a personal account highlighting several of my group's research contributions in metallo-organic chemistry over the past 40 years. Our early work focused primarily in stoichiometric structure/reactivity of transition metal-organic compounds and their use in organic synthesis. More recent efforts have centered on the discovery and development of new metal-catalyzed organic reactions via reactive metal-organic intermediates. The major research findings that are described here include (1) propargyl-cobalt complexes as electrophilic agents for C-C and C-Nu coupling; (2) the activation of carbon dioxide by metal complexes; (3) metal-promoted C-H nitrogenation reactions; (4) oxo-metal catalyzed deoxygenation reactions; and (5) catalyst discovery via dynamic templating with substrate- and transition-state analogues.

  6. Mixed-Methods Study of Online and Written Organic Chemistry Homework

    Science.gov (United States)

    Malik, Kinza; Martinez, Nylvia; Romero, Juan; Schubel, Skyler; Janowicz, Philip A.

    2014-01-01

    Connect for organic chemistry is an online learning tool that gives students the opportunity to learn about all aspects of organic chemistry through the ease of the digital world. This research project consisted of two fundamental questions. The first was to discover whether there was a difference in undergraduate organic chemistry content…

  7. Organic Chemistry Educators' Perspectives on Fundamental Concepts and Misconceptions: An Exploratory Study

    Science.gov (United States)

    Duis, Jennifer M.

    2011-01-01

    An exploratory study was conducted with 23 organic chemistry educators to discover what general chemistry concepts they typically review, the concepts they believe are fundamental to introductory organic chemistry, the topics students find most difficult in the subject, and the misconceptions they observe in undergraduate organic chemistry…

  8. Supramolecular chemistry: from molecular information towards self-organization and complex matter

    International Nuclear Information System (INIS)

    Lehn, Jean-Marie

    2004-01-01

    supramolecular polymers and liquid crystals, and provide an original approach to nanoscience and nanotechnology. In particular, the spontaneous but controlled generation of well-defined, functional supramolecular architectures of nanometric size through self-organization represents a means of performing programmed engineering and processing of nanomaterials. Supramolecular chemistry is intrinsically a dynamic chemistry, in view of the lability of the interactions connecting the molecular components of a supramolecular entity and the resulting ability of supramolecular species to exchange their constituents. The same holds for molecular chemistry when a molecular entity contains covalent bonds that may form and break reversibly, so as to make possible a continuous change in constitution and structure by reorganization and exchange of building blocks. This behaviour defines a constitutional dynamic chemistry that allows self-organization by selection as well as by design at both the molecular and supramolecular levels. Whereas self-organization by design strives to achieve full control over the output molecular or supramolecular entity by explicit programming, self-organization by selection operates on dynamic constitutional diversity in response to either internal or external factors to achieve adaptation in a Darwinistic fashion. The merging of the features, information and programmability, dynamics and reversibility, constitution and structural diversity, points towards the emergence of adaptative and evolutionary chemistry. Together with the corresponding fields of physics and biology, it constitutes a science of informed matter, of organized, adaptative complex matter

  9. Recent Discoveries and Future Challenges in Atmospheric Organic Chemistry.

    Science.gov (United States)

    Glasius, Marianne; Goldstein, Allen H

    2016-03-15

    Earth's atmosphere contains a multitude of organic compounds, which differ by orders of magnitude regarding fundamental properties such as volatility, reactivity, and propensity to form cloud droplets, affecting their impact on global climate and human health. Despite recent major research efforts and advances, there are still substantial gaps in understanding of atmospheric organic chemistry, hampering efforts to understand, model, and mitigate environmental problems such as aerosol formation in both polluted urban and more pristine regions. The analytical toolbox available for chemists to study atmospheric organic components has expanded considerably during the past decade, opening new windows into speciation, time resolution and detection of reactive and semivolatile compounds at low concentrations. This has provided unprecedented opportunities, but also unveiled new scientific challenges. Specific groundbreaking examples include the role of epoxides in aerosol formation especially from isoprene, the importance of highly oxidized, reactive organics in air-surface processes (whether atmosphere-biosphere exchange or aerosols), as well as the extent of interactions of anthropogenic and biogenic emissions and the resulting impact on atmospheric organic chemistry.

  10. Exploration of the central dogma at the interface of chemistry and biology: 2010 Yale Chemical Biology Symposium.

    Science.gov (United States)

    Zhou, Alice Qinhua

    2010-09-01

    Ever since the term "central dogma" was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year's Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology.

  11. Single Molecule Spectroscopy in Chemistry, Physics and Biology Nobel Symposium

    CERN Document Server

    Gräslund, Astrid; Widengren, Jerker

    2010-01-01

    Written by the leading experts in the field, this book describes the development and current state-of-the-art in single molecule spectroscopy. The application of this technique, which started 1989, in physics, chemistry and biosciences is displayed.

  12. Getting the chemistry right: protonation, tautomers and the importance of H atoms in biological chemistry.

    Science.gov (United States)

    Bax, Ben; Chung, Chun Wa; Edge, Colin

    2017-02-01

    There are more H atoms than any other type of atom in an X-ray crystal structure of a protein-ligand complex, but as H atoms only have one electron they diffract X-rays weakly and are `hard to see'. The positions of many H atoms can be inferred by our chemical knowledge, and such H atoms can be added with confidence in `riding positions'. For some chemical groups, however, there is more ambiguity over the possible hydrogen placements, for example hydroxyls and groups that can exist in multiple protonation states or tautomeric forms. This ambiguity is far from rare, since about 25% of drugs have more than one tautomeric form. This paper focuses on the most common, `prototropic', tautomers, which are isomers that readily interconvert by the exchange of an H atom accompanied by the switch of a single and an adjacent double bond. Hydrogen-exchange rates and different protonation states of compounds (e.g. buffers) are also briefly discussed. The difference in heavy (non-H) atom positions between two tautomers can be small, and careful refinement of all possible tautomers may single out the likely bound ligand tautomer. Experimental methods to determine H-atom positions, such as neutron crystallography, are often technically challenging. Therefore, chemical knowledge and computational approaches are frequently used in conjugation with experimental data to deduce the bound tautomer state. Proton movement is a key feature of many enzymatic reactions, so understanding the orchestration of hydrogen/proton motion is of critical importance to biological chemistry. For example, structural studies have suggested that, just as a chemist may use heat, some enzymes use directional movement to protonate specific O atoms on phosphates to catalyse phosphotransferase reactions. To inhibit `wriggly' enzymes that use movement to effect catalysis, it may be advantageous to have inhibitors that can maintain favourable contacts by adopting different tautomers as the enzyme `wriggles'.

  13. Integrative Biological Chemistry Program Includes the Use of Informatics Tools, GIS and SAS Software Applications

    Science.gov (United States)

    D'Souza, Malcolm J.; Kashmar, Richard J.; Hurst, Kent; Fiedler, Frank; Gross, Catherine E.; Deol, Jasbir K.; Wilson, Alora

    2015-01-01

    Wesley College is a private, primarily undergraduate minority-serving institution located in the historic district of Dover, Delaware (DE). The College recently revised its baccalaureate biological chemistry program requirements to include a one-semester Physical Chemistry for the Life Sciences course and project-based experiential learning…

  14. Linking soil biology and chemistry in biological soil crust using isolate exometabolomics.

    Science.gov (United States)

    Swenson, Tami L; Karaoz, Ulas; Swenson, Joel M; Bowen, Benjamin P; Northen, Trent R

    2018-01-02

    Metagenomic sequencing provides a window into microbial community structure and metabolic potential; however, linking these data to exogenous metabolites that microorganisms process and produce (the exometabolome) remains challenging. Previously, we observed strong exometabolite niche partitioning among bacterial isolates from biological soil crust (biocrust). Here we examine native biocrust to determine if these patterns are reproduced in the environment. Overall, most soil metabolites display the expected relationship (positive or negative correlation) with four dominant bacteria following a wetting event and across biocrust developmental stages. For metabolites that were previously found to be consumed by an isolate, 70% are negatively correlated with the abundance of the isolate's closest matching environmental relative in situ, whereas for released metabolites, 67% were positively correlated. Our results demonstrate that metabolite profiling, shotgun sequencing and exometabolomics may be successfully integrated to functionally link microbial community structure with environmental chemistry in biocrust.

  15. What are the Limitations of Enzymes in Synthetic Organic Chemistry?

    Science.gov (United States)

    Reetz, Manfred T

    2016-12-01

    Enzymes have been used in organic chemistry and biotechnology for 100 years, but their widespread application has been prevented by a number of limitations, including the often-observed limited thermostability, narrow substrate scope, and low or wrong stereo- and/or regioselectivity. Directed evolution provides a means to address and generally solve these problems, especially since recent methodology development has made this protein engineering method faster, more efficient, and more reliable than in the past. This Darwinian approach to asymmetric catalysis has led to a number of industrial applications. Metabolic-pathway engineering, mutasynthesis, and fermentation are likewise enzyme-based techniques that enrich chemistry. This account outlines the scope, and particularly, the limitations, of biocatalysis. The complementary nature of enzymes and man-made catalysts is emphasized. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Coordination Compounds in Biology-The Chemistry of Vitamin B12 ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 16; Issue 12. Coordination Compounds in Biology - The Chemistry of Vitamin B12 and Model Compounds. K Hussian Reddy. Volume 16 Issue 12 December 2011 pp 1273-1283 ...

  17. Coordination chemistry and biological activity of 5'-OH modified quinoline-B12 derivatives.

    Science.gov (United States)

    Zelenka, Karel; Brandl, Helmut; Spingler, Bernhard; Zelder, Felix

    2011-10-14

    The consequences of structural modifications at the 5'-OH ribofuranotide moiety of quinoline modified B12 derivatives are discussed in regard of the coordination chemistry, the electrochemical properties and the biological behaviour of the compound.

  18. Determination of Rate Constants for Ouabain Inhibition of Adenosine Triphosphatase: An Undergraduate Biological Chemistry Laboratory Experiment

    Science.gov (United States)

    Sall, Eri; And Others

    1978-01-01

    Describes an undergraduate biological chemistry laboratory experiment which provides students with an example of pseudo-first-order kinetics with the cardiac glycoside inhibition of mammalism sodium and potassium transport. (SL)

  19. The chemistry of separations ligand degradation by organic radical cations

    International Nuclear Information System (INIS)

    Mezyk, S.P.; Horne, G.P.; Mincher, B.J.; Zalupski, P.R.; Cook, A.R.; Wishart, J.F.

    2016-01-01

    Solvent based extractions of used nuclear fuel use designer ligands in an organic phase extracting ligand complexed metal ions from an acidic aqueous phase. These extractions will be performed in highly radioactive environments, and the radiation chemistry of all these complexing agents and their diluents will play a major role in determining extraction efficiency, separation factors, and solvent-recycle longevity. Although there has been considerable effort in investigating ligand damage occurring in acidic water radiolysis conditions, only minimal fundamental kinetic and mechanistic data has been reported for the degradation of extraction ligands in the organic phase. Extraction solvent phases typically use normal alkanes such as dodecane, TPH, and kerosene as diluents. The radiolysis of such diluents produce a mixture of radical cations (R .+ ), carbon-centered radicals (R . ), solvated electrons, and molecular products such as hydrogen. Typically, the radical species will preferentially react with the dissolved oxygen present to produce relatively inert peroxyl radicals. This isolates the alkane radical cation species, R .+ as the major radiolytically-induced organic species that can react with, and degrade, extraction agents in this phase. Here we report on our recent studies of organic radical cation reactions with 2 ligands: CMPO and TODGA. Elucidating these parameters, and combining them with the known acidic aqueous phase chemistry, will allow a full, fundamental, understanding of the impact of radiation on solvent extraction based separation processes to be achieved. (authors)

  20. Testing the Vibrational Theory of Olfaction: A Bio-Organic Chemistry Laboratory Experiment Using Hooke's Law and Chirality

    Science.gov (United States)

    Muthyala, Rajeev S.; Butani, Deepali; Nelson, Michelle; Tran, Kiet

    2017-01-01

    Sense of smell is one of the important senses that enables us to interact with our environment. The molecular basis of olfactory signal transduction is a fascinating area for organic chemistry educators to explore in terms of developing undergraduate laboratory activities at the interface of chemistry and biology. In this paper, a guided-inquiry…

  1. Introducing Bond-Line Organic Structures in High School Biology: An Activity that Incorporates Pleasant-Smelling Molecules

    Science.gov (United States)

    Rios, Andro C.; French, Gerald

    2011-01-01

    Chemical education occurs in settings other than just the chemistry classroom. High school biology courses are frequently where students are introduced to organic molecules and their importance to cellular chemistry. However, structural representations are often intimidating because students have not been introduced to the language. As part of a…

  2. Synthesis and Reactivity of Propargylamines in Organic Chemistry.

    Science.gov (United States)

    Lauder, Kate; Toscani, Anita; Scalacci, Nicolò; Castagnolo, Daniele

    2017-12-27

    Propargylamines are a versatile class of compounds which find broad application in many fields of chemistry. This review aims to describe the different strategies developed so far for the synthesis of propargylamines and their derivatives as well as to highlight their reactivity and use as building blocks in the synthesis of chemically relevant organic compounds. In the first part of the review, the different synthetic approaches to synthesize propargylamines, such as A 3 couplings and C-H functionalization of alkynes, have been described and organized on the basis of the catalysts employed in the syntheses. Both racemic and enantioselective approaches have been reported. In the second part, an overview of the transformations of propargylamines into heterocyclic compounds such as pyrroles, pyridines, thiazoles, and oxazoles, as well as other relevant organic derivatives, is presented.

  3. Biocatalysis in organic chemistry and biotechnology: past, present, and future.

    Science.gov (United States)

    Reetz, Manfred T

    2013-08-28

    Enzymes as catalysts in synthetic organic chemistry gained importance in the latter half of the 20th century, but nevertheless suffered from two major limitations. First, many enzymes were not accessible in large enough quantities for practical applications. The advent of recombinant DNA technology changed this dramatically in the late 1970s. Second, many enzymes showed a narrow substrate scope, often poor stereo- and/or regioselectivity and/or insufficient stability under operating conditions. With the development of directed evolution beginning in the 1990s and continuing to the present day, all of these problems can be addressed and generally solved. The present Perspective focuses on these and other developments which have popularized enzymes as part of the toolkit of synthetic organic chemists and biotechnologists. Included is a discussion of the scope and limitation of cascade reactions using enzyme mixtures in vitro and of metabolic engineering of pathways in cells as factories for the production of simple compounds such as biofuels and complex natural products. Future trends and problems are also highlighted, as is the discussion concerning biocatalysis versus nonbiological catalysis in synthetic organic chemistry. This Perspective does not constitute a comprehensive review, and therefore the author apologizes to those researchers whose work is not specifically treated here.

  4. Electron spin interactions in chemistry and biology fundamentals, methods, reactions mechanisms, magnetic phenomena, structure investigation

    CERN Document Server

    Likhtenshtein, Gertz

    2016-01-01

    This book presents the versatile and pivotal role of electron spin interactions in nature. It provides the background, methodologies and tools for basic areas related to spin interactions, such as spin chemistry and biology, electron transfer, light energy conversion, photochemistry, radical reactions, magneto-chemistry and magneto-biology. The book also includes an overview of designing advanced magnetic materials, optical and spintronic devices and photo catalysts. This monograph appeals to scientists and graduate students working in the areas related to spin interactions physics, biophysics, chemistry and chemical engineering.

  5. Modern electronic structure theory and applications in organic chemistry

    CERN Document Server

    Davidson, ER

    1997-01-01

    This volume focuses on the use of quantum theory to understand and explain experiments in organic chemistry. High level ab initio calculations, when properly performed, are useful in making quantitative distinctions between various possible interpretations of structures, reactions and spectra. Chemical reasoning based on simpler quantum models is, however, essential to enumerating the likely possibilities. The simpler models also often suggest the type of wave function likely to be involved in ground and excited states at various points along reaction paths. This preliminary understanding is n

  6. Modules for Introducing Organometallic Reactions: A Bridge between Organic and Inorganic Chemistry

    Science.gov (United States)

    Schaller, Chris P.; Graham, Kate J.; Johnson, Brian J.

    2015-01-01

    Transition metal organometallic reactions have become increasingly important in the synthesis of organic molecules. A new approach has been developed to introduce organometallic chemistry, along with organic and inorganic chemistry, at the foundational level. This change highlights applications of organometallic chemistry that have dramatically…

  7. The integration of the contents of the subject Physics-Chemistry (I in Biology-Chemistry specialty

    Directory of Open Access Journals (Sweden)

    M. Sc. Luis AZCUY LORENZ

    2017-12-01

    Full Text Available This work is the result of a research task developed in the Natural Sciences Education Department during 2013-2014 academic year, and it emerged from the necessity of solving some insufficiencies in the use of the real potentialities offered by the content of the subject Physics-Chemistry (I, that is part of the curriculum of the Biology-Chemistry career. Its main objective is to offer a set of exercises to contribute to achieve the integration of contents from the subject Physics-chemistry (I in the mentioned career at «Ignacio Agramonte Loynaz» University of Camaguey. The exercises proposed are characterized for being related to the real practice and to other subjects of the career. Their implementation through review lessons, partial tests and final evaluations during the formative experiment made possible a better academic result in the learners overall performance.

  8. EFFECTS OF 5E LEARNING CYCLE ON STUDENTS ACHIEVEMENT IN BIOLOGY AND CHEMISTRY

    Directory of Open Access Journals (Sweden)

    Patrick Osawaru Ajaja,

    2012-01-01

    Full Text Available The major purpose of this study was to determine the effects of learning cycle as an instructional strategy on biology andchemistry students achievement. To guide this study, six research hypotheses were stated and tested at 0.05 level ofsignificance. The design of this study was 2x2x3x6 Pre-test Post-test non-equivalent control group quasi experimental design.These included two instructional groups (experimental and control groups, sex (male and female, repeated testing (Pre,Post and follow-up tests, and six weeks of experience. The samples of the study included six senior secondary schools, 112science students, and 12 biology and chemistry teachers. The instruments used for this study were: teacher’s questionnaireon knowledge and use of learning cycle (KULC; and Biology and Chemistry Achievement Test (BCAT. The data collected wereanalyzed with simple percentage, Analysis of Covariance (ANCOVA and student t-test statistics. The major findings of thestudy included that only 30.43% and 26.31% of biology and chemistry teachers have the knowledge that learning cycle is aninstructional method; all the biology and chemistry teachers sampled have never used learning cycle as an instructionalmethod; learning cycle had a significant effect on students achievement in biology and chemistry; students taught withlearning cycle significantly achieved better in biology/chemistry Post-test than those taught with lecture method; the posttestscores of students in the learning cycle group increased over the period of experience; non-significant difference in Posttestscores between males and females taught with learning cycle; non-significant interaction effect between method andsex on achievement; and a significant higher retention of biology and chemistry knowledge by students taught with learningcycle than those taught with lecture method. It was concluded that the method seems an appropriate instructional modelthat could be used to solve the problems of

  9. Ethnopharmacology, Chemistry and Biological Properties of Four Malian Medicinal Plants

    OpenAIRE

    Karl Egil Malterud

    2017-01-01

    The ethnopharmacology, chemistry and pharmacology of four Malian medicinal plants, Biophytum umbraculum, Burkea africana, Lannea velutina and Terminalia macroptera are reviewed. These plants are used by traditional healers against numerous ailments: malaria, gastrointestinal diseases, wounds, sexually transmitted diseases, insect bites and snake bites, etc. The scientific evidence for these uses is, however, limited. From the chemical and pharmacological evidence presented here, it seems poss...

  10. How chemistry supports cell biology: the chemical toolbox at your service.

    Science.gov (United States)

    Wijdeven, Ruud H; Neefjes, Jacques; Ovaa, Huib

    2014-12-01

    Chemical biology is a young and rapidly developing scientific field. In this field, chemistry is inspired by biology to create various tools to monitor and modulate biochemical and cell biological processes. Chemical contributions such as small-molecule inhibitors and activity-based probes (ABPs) can provide new and unique insights into previously unexplored cellular processes. This review provides an overview of recent breakthroughs in chemical biology that are likely to have a significant impact on cell biology. We also discuss the application of several chemical tools in cell biology research. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Exploration of the Central Dogma at the Interface of Chemistry and Biology

    Science.gov (United States)

    Zhou, Alice Qinhua

    2010-01-01

    Ever since the term “central dogma” was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year’s Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology. PMID:20885900

  12. Exploration of the Central Dogma at the Interface of Chemistry and Biology

    OpenAIRE

    Zhou, Alice Qinhua

    2010-01-01

    Ever since the term ?central dogma? was coined in 1958, researchers have sought to control information flow from nucleic acids to proteins. Talks delivered by Drs. Anna Pyle and Hiroaki Suga at this year?s Chemical Biology Symposium at Yale in May 2010 applauded recent advances in this area, at the interface between chemistry and biology.

  13. On the Applicability of the Green Chemistry Principles to Sustainability of Organic Matter on Asteroids

    OpenAIRE

    Vera M. Kolb

    2010-01-01

    The connection between astrobiology and green chemistry represents a new approach to sustainability of organic matter on asteroids or similar bodies. Green chemistry is chemistry which is environmentally friendly. One obvious way for chemistry to be green is to use water as a solvent, instead of more toxic organic solvents. Many astrobiological reactions occur in the aqueous medium, for example in the prebiotic soup or during the aqueous alteration period on asteroids. Thus any advances in th...

  14. Benchmarking uranyl peroxide capsule chemistry in organic media

    International Nuclear Information System (INIS)

    Neal, Harrison A.; Nyman, May; Szymanowski, Jennifer; Fein, Jeremy B.; Burns, Peter C.

    2017-01-01

    Uranyl peroxide capsules are a recent addition to polyoxometalate (POM) chemistry. Ten years of development has ensued only in water, while transition metal POMs are commonly exploited in aqueous and organic media, controlled by counterions or ligation to render the clusters hydrophilic or hydrophobic. Here, new uranyl POM behavior is recognized in organic media, including (1) stabilization and immobilization of encapsulated hydrophilic countercations, identified by Li nuclear magnetic resonance (NMR) spectroscopy, (2) formation of new cluster species upon phase transfer, (3) extraction of uranyl clusters from different starting materials including simulated spent nuclear fuel, (4) selective phase transfer of one cluster type from a mixture, and (5) phase transfer of clusters from both acidic and alkaline media. The capsule morphology of the uranyl POMs renders accurate characterization by X-ray scattering, including the distinction of geometrically similar clusters. Compositional analysis of the aqueous phase post-extraction provided a quantitative determination of the ion exchange process that enables transfer of the clusters into the organic phase. Preferential partitioning of uranyl POMs into organic media presents new frontiers in metal ion behavior and chemical reactions in the confined space of the cluster capsules in hydrophobic media, as well as the reactivity of clusters at the organic/aqueous interface. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  15. Benchmarking uranyl peroxide capsule chemistry in organic media

    Energy Technology Data Exchange (ETDEWEB)

    Neal, Harrison A.; Nyman, May [Department of Chemistry, Oregon State University, Corvallis, OR (United States); Szymanowski, Jennifer; Fein, Jeremy B.; Burns, Peter C. [Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN (United States)

    2017-01-03

    Uranyl peroxide capsules are a recent addition to polyoxometalate (POM) chemistry. Ten years of development has ensued only in water, while transition metal POMs are commonly exploited in aqueous and organic media, controlled by counterions or ligation to render the clusters hydrophilic or hydrophobic. Here, new uranyl POM behavior is recognized in organic media, including (1) stabilization and immobilization of encapsulated hydrophilic countercations, identified by Li nuclear magnetic resonance (NMR) spectroscopy, (2) formation of new cluster species upon phase transfer, (3) extraction of uranyl clusters from different starting materials including simulated spent nuclear fuel, (4) selective phase transfer of one cluster type from a mixture, and (5) phase transfer of clusters from both acidic and alkaline media. The capsule morphology of the uranyl POMs renders accurate characterization by X-ray scattering, including the distinction of geometrically similar clusters. Compositional analysis of the aqueous phase post-extraction provided a quantitative determination of the ion exchange process that enables transfer of the clusters into the organic phase. Preferential partitioning of uranyl POMs into organic media presents new frontiers in metal ion behavior and chemical reactions in the confined space of the cluster capsules in hydrophobic media, as well as the reactivity of clusters at the organic/aqueous interface. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Seeking the chemical roots of darwinism: bridging between chemistry and biology.

    Science.gov (United States)

    Pross, Addy

    2009-08-24

    Chemistry and biology are intimately connected sciences yet the chemistry-biology interface remains problematic and central issues regarding the very essence of living systems remain unresolved. In this essay we build on a kinetic theory of replicating systems that encompasses the idea that there are two distinct kinds of stability in nature-thermodynamic stability, associated with "regular" chemical systems, and dynamic kinetic stability, associated with replicating systems. That fundamental distinction is utilized to bridge between chemistry and biology by demonstrating that within the parallel world of replicating systems there is a second law analogue to the second law of thermodynamics, and that Darwinian theory may, through scientific reductionism, be related to that second law analogue. Possible implications of these ideas to the origin of life problem and the relationship between chemical emergence and biological evolution are discussed.

  17. Alcohol Pharmacology Education Partnership: Using Chemistry and Biology Concepts To Educate High School Students about Alcohol.

    Science.gov (United States)

    Godin, Elizabeth A; Kwiek, Nicole; Sikes, Suzanne S; Halpin, Myra J; Weinbaum, Carolyn A; Burgette, Lane F; Reiter, Jerome P; Schwartz-Bloom, Rochelle D

    2014-02-11

    We developed the Alcohol Pharmacology Education Partnership (APEP), a set of modules designed to integrate a topic of interest (alcohol) with concepts in chemistry and biology for high school students. Chemistry and biology teachers ( n = 156) were recruited nationally to field-test APEP in a controlled study. Teachers obtained professional development either at a conference-based workshop (NSTA or NCSTA) or via distance learning to learn how to incorporate the APEP modules into their teaching. They field-tested the modules in their classes during the following year. Teacher knowledge of chemistry and biology concepts increased significantly following professional development, and was maintained for at least a year. Their students ( n = 14 014) demonstrated significantly higher scores when assessed for knowledge of both basic and advanced chemistry and biology concepts compared to students not using APEP modules in their classes the previous year. Higher scores were achieved as the number of modules used increased. These findings are consistent with our previous studies, demonstrating higher scores in chemistry and biology after students use modules that integrate topics interesting to them, such as drugs (the Pharmacology Education Partnership).

  18. Integrating pharmacology topics in high school biology and chemistry classes improves performance

    Science.gov (United States)

    Schwartz-Bloom, Rochelle D.; Halpin, Myra J.

    2003-11-01

    Although numerous programs have been developed for Grade Kindergarten through 12 science education, evaluation has been difficult owing to the inherent problems conducting controlled experiments in the typical classroom. Using a rigorous experimental design, we developed and tested a novel program containing a series of pharmacology modules (e.g., drug abuse) to help high school students learn basic principles in biology and chemistry. High school biology and chemistry teachers were recruited for the study and they attended a 1-week workshop to learn how to integrate pharmacology into their teaching. Working with university pharmacology faculty, they also developed classroom activities. The following year, teachers field-tested the pharmacology modules in their classrooms. Students in classrooms using the pharmacology topics scored significantly higher on a multiple choice test of basic biology and chemistry concepts compared with controls. Very large effect sizes (up to 1.27 standard deviations) were obtained when teachers used as many as four modules. In addition, biology students increased performance on chemistry questions and chemistry students increased performance on biology questions. Substantial gains in achievement may be made when high school students are taught science using topics that are interesting and relevant to their own lives.

  19. Alcohol Pharmacology Education Partnership: Using Chemistry and Biology Concepts To Educate High School Students about Alcohol

    Science.gov (United States)

    2015-01-01

    We developed the Alcohol Pharmacology Education Partnership (APEP), a set of modules designed to integrate a topic of interest (alcohol) with concepts in chemistry and biology for high school students. Chemistry and biology teachers (n = 156) were recruited nationally to field-test APEP in a controlled study. Teachers obtained professional development either at a conference-based workshop (NSTA or NCSTA) or via distance learning to learn how to incorporate the APEP modules into their teaching. They field-tested the modules in their classes during the following year. Teacher knowledge of chemistry and biology concepts increased significantly following professional development, and was maintained for at least a year. Their students (n = 14 014) demonstrated significantly higher scores when assessed for knowledge of both basic and advanced chemistry and biology concepts compared to students not using APEP modules in their classes the previous year. Higher scores were achieved as the number of modules used increased. These findings are consistent with our previous studies, demonstrating higher scores in chemistry and biology after students use modules that integrate topics interesting to them, such as drugs (the Pharmacology Education Partnership). PMID:24803686

  20. Ethnopharmacology, Chemistry and Biological Properties of Four Malian Medicinal Plants.

    Science.gov (United States)

    Malterud, Karl Egil

    2017-02-21

    The ethnopharmacology, chemistry and pharmacology of four Malian medicinal plants, Biophytum umbraculum , Burkea africana , Lannea velutina and Terminalia macroptera are reviewed. These plants are used by traditional healers against numerous ailments: malaria, gastrointestinal diseases, wounds, sexually transmitted diseases, insect bites and snake bites, etc. The scientific evidence for these uses is, however, limited. From the chemical and pharmacological evidence presented here, it seems possible that the use in traditional medicine of these plants may have a rational basis, although more clinical studies are needed.

  1. Ethnopharmacology, Chemistry and Biological Properties of Four Malian Medicinal Plants

    Directory of Open Access Journals (Sweden)

    Karl Egil Malterud

    2017-02-01

    Full Text Available The ethnopharmacology, chemistry and pharmacology of four Malian medicinal plants, Biophytum umbraculum, Burkea africana, Lannea velutina and Terminalia macroptera are reviewed. These plants are used by traditional healers against numerous ailments: malaria, gastrointestinal diseases, wounds, sexually transmitted diseases, insect bites and snake bites, etc. The scientific evidence for these uses is, however, limited. From the chemical and pharmacological evidence presented here, it seems possible that the use in traditional medicine of these plants may have a rational basis, although more clinical studies are needed.

  2. Applying combinatorial chemistry and biology to food research.

    Science.gov (United States)

    Wong, Dominic; Robertson, George

    2004-12-01

    In the past decade combinatorial chemistry has become a major focus of research activity in the pharmaceutical industry for accelerating the development of novel therapeutic compounds. The same combinatorial strategies could be applied to a broad spectrum of areas in agricultural and food research, including food safety and nutrition, development of product ingredients, and processing and conversion of natural products. In contrast to "rational design", the combinatorial approach relies on molecular diversity and high-throughput screening. The capability of exploring the structural and functional limits of a vast population of diverse chemical and biochemical molecules makes it possible to expedite the creation and isolation of compounds of desirable and useful properties. Several studies in recent years have demonstrated the utility of combinatorial methods for food research. These include the discovery of synthetic antimicrobial, antioxidative, and aflatoxin-binding peptides, the identification and analysis of unique flavor compounds, the generation of new enzyme inhibitors, the development of therapeutic antibodies for botulinum neurotoxins, the synthesis of unnatural polyketides and carotenoids, and the modification of food enzymes with novel properties. The results of such activities could open a large area of applications with potential benefits to the food industry. This review describes the current techniques of combinatorial chemistry and their applications, with emphasis on examples in food science research.

  3. Using structure-based organic chemistry online tutorials with automated correction for student practice and review

    OpenAIRE

    O'Sullivan, Timothy P.; Hargaden, Gráinne C.

    2014-01-01

    This article describes the development and implementation of an open-access organic chemistry question bank for online tutorials and assessments at University College Cork and Dublin Institute of Technology. SOCOT (structure-based organic chemistry online tutorials) may be used to supplement traditional small-group tutorials, thereby allowing students to develop essential problem-solving skills in organic chemistry. This online approach may be used for both formative and summative assessment....

  4. Concept-Oriented Task Design: Making Purposeful Case Comparisons in Organic Chemistry

    Science.gov (United States)

    Graulich, Nicole; Schween, Michael

    2018-01-01

    Acquiring conceptual understanding seems to be one of the main challenges students face when studying organic chemistry. Traditionally, organic chemistry presents an extensive variety of chemical transformations, which often lead students to recall an organic transformation rather than apply conceptual knowledge. Strong surface level focus and…

  5. Organic Chemistry Students' Ideas about Nucleophiles and Electrophiles: The Role of Charges and Mechanisms

    Science.gov (United States)

    Anzovino, Mary E.; Bretz, Stacey Lowery

    2015-01-01

    Organic chemistry students struggle with reaction mechanisms and the electron-pushing formalism (EPF) used by practicing organic chemists. Faculty have identified an understanding of nucleophiles and electrophiles as one conceptual prerequisite to mastery of the EPF, but little is known about organic chemistry students' knowledge of nucleophiles…

  6. Irradiated Benzene Ice Provides Clues to Meteoritic Organic Chemistry

    Science.gov (United States)

    Callahan, Michael Patrick; Gerakines, Perry Alexander; Martin, Mildred G.; Hudson, Reggie L.; Peeters, Zan

    2013-01-01

    Aromatic hydrocarbons account for a significant portion of the organic matter in carbonaceous chondrite meteorites, as a component of both the low molecular weight, solvent-extractable compounds and the insoluble organic macromolecular material. Previous work has suggested that the aromatic compounds in carbonaceous chondrites may have originated in the radiation-processed icy mantles of interstellar dust grains. Here we report new studies of the organic residue made from benzene irradiated at 19 K by 0.8 MeV protons. Polyphenyls with up to four rings were unambiguously identified in the residue by gas chromatography-mass spectrometry. Atmospheric pressure photoionization Fourier transform mass spectrometry was used to determine molecular composition, and accurate mass measurements suggested the presence of polyphenyls, partially hydrogenated polyphenyls, and other complex aromatic compounds. The profile of low molecular weight compounds in the residue compared well with extracts from the Murchison and Orgueil meteorites. These results are consistent with the possibility that solid phase radiation chemistry of benzene produced some of the complex aromatics found in meteorites.

  7. Different pathways but same result? Comparing chemistry and biological effects of burned and decomposed litter

    Science.gov (United States)

    Mazzoleni, Stefano; Bonanomi, Giuliano; Incerti, Guido; El-Gawad, Ahmed M. Abd; Sarker, Tushar Chandra; Cesarano, Gaspare; Saulino, Luigi; Saracino, Antonio; Castro Rego, Francisco

    2017-04-01

    Litter burning and biological decomposition are oxidative processes co-occurring in many terrestrial ecosystems, producing organic matter with different chemical properties and differently affecting plant growth and soil microbial activity. Here, we tested the chemical convergence hypothesis (i.e. materials with different initial chemistry tend to converge towards a common profile, with similar biological effects, as the oxidative process advances) for burning and decomposition. We compared the molecular composition of 63 organic materials - 7 litter types either fresh, decomposed for 30, 90, 180 days, or heated at 100, 200, 300, 400, 500 °C - as assessed by 13C NMR. We used litter water extracts (5% dw) as treatments in bioassays on plant (Lepidium sativum) and fungal (Aspergillus niger) growth, and a washed quartz sand amended with litter materials (0.5 % dw) to assess heterotrophic respiration by CO2 flux chamber. We observed different molecular variations for materials either burning (i.e. a sharp increase of aromatic C and a decrease of most other fractions above 200 °C) or decomposing (i.e. early increase of alkyl, methoxyl and N-alkyl C and decrease of O-alkyl and di-O-alkyl C fractions). Soil respiration and fungal growth progressively decreased with litter age and temperature. Plant growth underwent an inhibitory effect by untreated litter, more and less rapidly released over decomposing and burning materials, respectively. Correlation analysis between NMR and bioassay data showed that opposite responses for soil respiration and fungi, compared to plants, are related to essentially the same C molecular types. Our findings suggest a functional convergence of decomposed and burnt organic substrates, emerging from the balance between the bioavailability of labile C sources and the presence of recalcitrant and pyrogenic compounds, oppositely affecting different trophic levels.

  8. ZINC: a free tool to discover chemistry for biology.

    Science.gov (United States)

    Irwin, John J; Sterling, Teague; Mysinger, Michael M; Bolstad, Erin S; Coleman, Ryan G

    2012-07-23

    ZINC is a free public resource for ligand discovery. The database contains over twenty million commercially available molecules in biologically relevant representations that may be downloaded in popular ready-to-dock formats and subsets. The Web site also enables searches by structure, biological activity, physical property, vendor, catalog number, name, and CAS number. Small custom subsets may be created, edited, shared, docked, downloaded, and conveyed to a vendor for purchase. The database is maintained and curated for a high purchasing success rate and is freely available at zinc.docking.org.

  9. What Does the Acid Ionization Constant Tell You? An Organic Chemistry Student Guide

    Science.gov (United States)

    Rossi, Robert D.

    2013-01-01

    Many students find the transition from first-year general chemistry to second-year organic chemistry a daunting task. There are many reasons for this, not the least of which is their lack of a solid understanding and appreciation of the importance of some basic concepts and principles from general chemistry that play an extremely critical role in…

  10. The influence of the biological pump on ocean chemistry: implications for long-term trends in marine redox chemistry, the global carbon cycle, and marine animal ecosystems.

    Science.gov (United States)

    Meyer, K M; Ridgwell, A; Payne, J L

    2016-05-01

    The net export of organic matter from the surface ocean and its respiration at depth create vertical gradients in nutrient and oxygen availability that play a primary role in structuring marine ecosystems. Changes in the properties of this 'biological pump' have been hypothesized to account for important shifts in marine ecosystem structure, including the Cambrian explosion. However, the influence of variation in the behavior of the biological pump on ocean biogeochemistry remains poorly quantified, preventing any detailed exploration of how changes in the biological pump over geological time may have shaped long-term shifts in ocean chemistry, biogeochemical cycling, and ecosystem structure. Here, we use a 3-dimensional Earth system model of intermediate complexity to quantitatively explore the effects of the biological pump on marine chemistry. We find that when respiration of sinking organic matter is efficient, due to slower sinking or higher respiration rates, anoxia tends to be more prevalent and to occur in shallower waters. Consequently, the Phanerozoic trend toward less bottom-water anoxia in continental shelf settings can potentially be explained by a change in the spatial dynamics of nutrient cycling rather than by any change in the ocean phosphate inventory. The model results further suggest that the Phanerozoic decline in the prevalence ocean anoxia is, in part, a consequence of the evolution of larger phytoplankton, many of which produce mineralized tests. We hypothesize that the Phanerozoic trend toward greater animal abundance and metabolic demand was driven more by increased oxygen concentrations in shelf environments than by greater food (nutrient) availability. In fact, a lower-than-modern ocean phosphate inventory in our closed system model is unable to account for the Paleozoic prevalence of bottom-water anoxia. Overall, these model simulations suggest that the changing spatial distribution of photosynthesis and respiration in the oceans has

  11. Biological Actions of Artemisinin: Insights from Medicinal Chemistry Studies

    Directory of Open Access Journals (Sweden)

    Jian Li

    2010-03-01

    Full Text Available Artemisinins have become essential antimalarial drugs for increasingly widespread drug-resistant malaria strains. Although tremendous efforts have been devoted to decipher how this class of molecules works, their exact antimalarial mechanism is still an enigma. Several hypotheses have been proposed to explain their actions, including alkylation of heme by carbon-centered free radicals, interference with proteins such as the sarcoplasmic/endoplasmic calcium ATPase (SERCA, as well as damaging of normal mitochondrial functions. Besides artemisinins, other endoperoxides with various backbones have also been synthesized, some of which showed comparable or even higher antimalarial effects. It is noteworthy that among these artemisinin derivatives, some enantiomers displayed similar in vitro malaria killing efficacy. In this article, the proposed mechanisms of action of artemisinins are reviewed in light of medicinal chemistry findings characterized by efficacy-structure studies, with the hope of gaining more insight into how these potent drugs work.

  12. Click chemistry mediated functionalization of vertical nanowires for biological applications

    DEFF Research Database (Denmark)

    Vutti, Surendra; Schoffelen, Sanne; Bolinsson, Jessica

    2016-01-01

    is of general interest for biological studies. The attachment of a peptide substrate provided NW arrays for the detection of protease activity. In addition, green fluorescent protein was immobilized in a site-specific manner and recognized by antibody binding to demonstrate the proof-of-concept for the use...

  13. Green analytical chemistry - the use of surfactants as a replacement of organic solvents in spectroscopy

    Science.gov (United States)

    Pharr, Daniel Y.

    2017-07-01

    This chapter gives an introduction to the many practical uses of surfactants in analytical chemistry in replacing organic solvents to achieve greener chemistry. Taking a holistic approach, it covers some background of surfactants as chemical solvents, their properties and as green chemicals, including their environmental effects. The achievements of green analytical chemistry with micellar systems are reviewed in all the major areas of analytical chemistry where these reagents have been found to be useful.

  14. Essential concepts and underlying theories from physics, chemistry, and mathematics for "biochemistry and molecular biology" majors.

    Science.gov (United States)

    Wright, Ann; Provost, Joseph; Roecklein-Canfield, Jennifer A; Bell, Ellis

    2013-01-01

    Over the past two years, through an NSF RCN UBE grant, the ASBMB has held regional workshops for faculty members from around the country. The workshops have focused on developing lists of Core Principles or Foundational Concepts in Biochemistry and Molecular Biology, a list of foundational skills, and foundational concepts from Physics, Chemistry, and Mathematics that all Biochemistry or Molecular Biology majors must understand to complete their major coursework. The allied fields working group created a survey to validate foundational concepts from Physics, Chemistry, and Mathematics identified from participant feedback at various workshops. One-hundred twenty participants responded to the survey and 68% of the respondents answered yes to the question: "We have identified the following as the core concepts and underlying theories from Physics, Chemistry, and Mathematics that Biochemistry majors or Molecular Biology majors need to understand after they complete their major courses: 1) mechanical concepts from Physics, 2) energy and thermodynamic concepts from Physics, 3) critical concepts of structure from chemistry, 4) critical concepts of reactions from Chemistry, and 5) essential Mathematics. In your opinion, is the above list complete?" Respondents also delineated subcategories they felt should be included in these broad categories. From the results of the survey and this analysis the allied fields working group constructed a consensus list of allied fields concepts, which will help inform Biochemistry and Molecular Biology educators when considering the ASBMB recommended curriculum for Biochemistry or Molecular Biology majors and in the development of appropriate assessment tools to gauge student understanding of how these concepts relate to biochemistry and molecular biology. © 2013 by The International Union of Biochemistry and Molecular Biology.

  15. Peatland Organic Matter Chemistry Trends Over a Global Latitudinal Gradient

    Science.gov (United States)

    Verbeke, B. A.; Hodgkins, S. B.; Carson, M. A.; Lamit, L. J.; Lilleskov, E.; Chanton, J.

    2017-12-01

    Peatlands contain a significant amount of the global soil carbon, and the climate feedback of carbon cycling within these peatland systems is still relatively unknown. Organic matter composition of peatlands plays a major role in determining carbon storage, and while high latitude peatlands seem to be the most sensitive to climate change, a global picture of peat organic matter chemistry is required to improve predictions and models of greenhouse gas emissions fueled by peatland decomposition. The objective of this research is to test the hypothesis that carbohydrate content of peatlands near the equator will be lower than high latitude peatlands, while aromatic content will be higher. As a part of the Global Peatland Microbiome Project (GPMP), around 2000 samples of peat from 10 to 70 cm across a latitudinal gradient of 79 N to 53 S were measured with Fourier transform infrared spectroscopy (FTIR) to examine the organic matter functional groups of peat. Carbohydrate and aromatic content, as determined by FTIR, are useful proxies of decomposition potential and recalcitrance, respectively. We found a highly significant relationship between carbohydrate and aromatic content, latitude, and depth. Carbohydrate content of high latitude sites were significantly greater than at sites near the equator, in contrast to aromatic content which showed the opposite trend. It is also clear that carbohydrate content decreases with depth while aromatic content increases with depth. Higher carbohydrate content at higher latitudes indicates a greater potential for lability and resultant mineralization to form the greenhouse gases, carbon dioxide and methane, whereas the composition of low latitude peatlands is consistent with their apparent stability. We speculate that the combination of low carbohydrates and high aromatics at warmer locations near the equator could foreshadow the organic matter composition of high latitude peat transitioning to a more recalcitrant form with a

  16. Development and Implementation of a Two-Semester Introductory Organic-Bioorganic Chemistry Sequence: Conclusions from the First Six Years

    Science.gov (United States)

    Goess, Brian C.

    2014-01-01

    A two-semester second-year introductory organic chemistry sequence featuring one semester of accelerated organic chemistry followed by one semester of bioorganic chemistry is described. Assessment data collected over a six-year period reveal that such a course sequence can facilitate student mastery of fundamental organic chemistry in the first…

  17. Simple glycolipids of microbes: Chemistry, biological activity and metabolic engineering

    Directory of Open Access Journals (Sweden)

    Ahmad Mohammad Abdel-Mawgoud

    2018-03-01

    Full Text Available Glycosylated lipids (GLs are added-value lipid derivatives of great potential. Besides their interesting surface activities that qualify many of them to act as excellent ecological detergents, they have diverse biological activities with promising biomedical and cosmeceutical applications. Glycolipids, especially those of microbial origin, have interesting antimicrobial, anticancer, antiparasitic as well as immunomodulatory activities. Nonetheless, GLs are hardly accessing the market because of their high cost of production. We believe that experience of metabolic engineering (ME of microbial lipids for biofuel production can now be harnessed towards a successful synthesis of microbial GLs for biomedical and other applications. This review presents chemical groups of bacterial and fungal GLs, their biological activities, their general biosynthetic pathways and an insight on ME strategies for their production.

  18. Recent advances in the chemistry and biology of benzothiazoles.

    Science.gov (United States)

    Gill, Rupinder K; Rawal, Ravindra K; Bariwal, Jitender

    2015-03-01

    Benzothiazole is a privileged heterocyclic scaffold having a benzene ring fused with a five-membered thiazole ring. This moiety has attracted considerable attention because of its wide range of pharmacological activities such as antitubercular, antimicrobial, antimalarial, anticonvulsant, anthelmintic, analgesic, anti-inflammatory, antidiabetic, antitumor activity, etc. In the last few years, some novel benzothiazoles have been developed with varied biological activities. To access this scaffold in high yield and to introduce diversity, a variety of new synthetic methods have been invented. In this review, we highlight the development of novel benzothiazoles for various biological activities along with the best synthetic protocols for their synthesis. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Perception of the Relevance of Organic Chemistry in a German Pharmacy Students' Course.

    Science.gov (United States)

    Wehle, Sarah; Decker, Michael

    2016-04-25

    Objective. To investigate German pharmacy students' attitudes toward the relevance of organic chemistry training in Julius Maximilian University (JMU) of Würzburg with regard to subsequent courses in the curricula and in later prospective career options. Methods. Surveys were conducted in the second-year organic chemistry course (50 participants) as well as during the third-year and fourth-year lecture cycle on medicinal and pharmaceutical chemistry (66 participants) in 2014. Results. Students' attitudes were surprisingly consistent throughout the progress of the degree course. Students considered organic chemistry very relevant to the pharmacy study program (95% junior and 97% senior students), and of importance for their future pharmacy program (88% junior and 94% senior students). With regard to prospective career options, the perceived relevance was considerably lower and attitudes were less homogenous. Conclusions. German pharmacy students at JMU Würzburg consider organic chemistry of high relevance for medicinal chemistry and other courses in JMU's pharmacy program.

  20. ROSics: chemistry and proteomics of cysteine modifications in redox biology.

    Science.gov (United States)

    Kim, Hee-Jung; Ha, Sura; Lee, Hee Yoon; Lee, Kong-Joo

    2015-01-01

    Post-translational modifications (PTMs) occurring in proteins determine their functions and regulations. Proteomic tools are available to identify PTMs and have proved invaluable to expanding the inventory of these tools of nature that hold the keys to biological processes. Cysteine (Cys), the least abundant (1-2%) of amino acid residues, are unique in that they play key roles in maintaining stability of protein structure, participating in active sites of enzymes, regulating protein function and binding to metals, among others. Cys residues are major targets of reactive oxygen species (ROS), which are important mediators and modulators of various biological processes. It is therefore necessary to identify the Cys-containing ROS target proteins, as well as the sites and species of their PTMs. Cutting edge proteomic tools which have helped identify the PTMs at reactive Cys residues, have also revealed that Cys residues are modified in numerous ways. These modifications include formation of disulfide, thiosulfinate and thiosulfonate, oxidation to sulfenic, sulfinic, sulfonic acids and thiosulfonic acid, transformation to dehydroalanine (DHA) and serine, palmitoylation and farnesylation, formation of chemical adducts with glutathione, 4-hydroxynonenal and 15-deoxy PGJ2, and various other chemicals. We present here, a review of relevant ROS biology, possible chemical reactions of Cys residues and details of the proteomic strategies employed for rapid, efficient and sensitive identification of diverse and novel PTMs involving reactive Cys residues of redox-sensitive proteins. We propose a new name, "ROSics," for the science which describes the principles of mode of action of ROS at molecular levels. © 2014 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc.

  1. Adenine Synthesis in a Model Prebiotic Reaction: Connecting Origin of Life Chemistry with Biology

    OpenAIRE

    Anumukonda, Lakshmi N.; Young, Avery; Lynn, David G.; Buckley, Ragan; Warrayat, Amena; Graves, Christina L.; Bean, Heather D.; Hud, Nicholas V.

    2011-01-01

    Many high school laboratory experiments demonstrate concepts related to biological evolution, but few exist that allow students to investigate life?s chemical origins. This series of laboratory experiments has been developed to allow students to explore and appreciate the deep connection that exists between prebiotic chemistry, chemical evolution, and contemporary biological systems. In the first experiment of the series, students synthesize adenine, one of the purine nucleobases of DNA and R...

  2. Click Chemistry Mediated Functionalization of Vertical Nanowires for Biological Applications.

    Science.gov (United States)

    Vutti, Surendra; Schoffelen, Sanne; Bolinsson, Jessica; Buch-Månson, Nina; Bovet, Nicolas; Nygård, Jesper; Martinez, Karen L; Meldal, Morten

    2016-01-11

    Semiconductor nanowires (NWs) are gaining significant importance in various biological applications, such as biosensing and drug delivery. Efficient and controlled immobilization of biomolecules on the NW surface is crucial for many of these applications. Here, we present for the first time the use of the Cu(I) -catalyzed alkyne-azide cycloaddition and its strain-promoted variant for the covalent functionalization of vertical NWs with peptides and proteins. The potential of the approach was demonstrated in two complementary applications of measuring enzyme activity and protein binding, which is of general interest for biological studies. The attachment of a peptide substrate provided NW arrays for the detection of protease activity. In addition, green fluorescent protein was immobilized in a site-specific manner and recognized by antibody binding to demonstrate the proof-of-concept for the use of covalently modified NWs for diagnostic purposes using minute amounts of material. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Trends in metallo-organic chemistry of scandium, yttrium, and the lanthanides

    International Nuclear Information System (INIS)

    Singh, A.

    1994-01-01

    Several interesting aspects of the metallo-organic chemistry of group 3 and the lanthanides have been highlighted, which include: (a) the chemistry of a few notable organolanthanide compounds, alkoxo and aryloxo derivatives derived from sterically demanding ligands, (b) new trends in the chemistry of lanthanide heterometallic alkoxides, (c) an account of zero valent organometallics of yttrium and the lanthanides, and (d) aspects of agostic interactions in the lanthanide metallo-organic compounds. (author). 49 refs

  4. Analysis of the Effect of Sequencing Lecture and Laboratory Instruction on Student Learning and Motivation Towards Learning Chemistry in an Organic Chemistry Lecture Course

    Science.gov (United States)

    Pakhira, Deblina

    2012-01-01

    Exposure to organic chemistry concepts in the laboratory can positively affect student performance, learning new chemistry concepts and building motivation towards learning chemistry in the lecture. In this study, quantitative methods were employed to assess differences in student performance, learning, and motivation in an organic chemistry…

  5. Pre-Service Science Teachers' Pedagogical Content Knowledge in the Physics, Chemistry, and Biology Topics

    Science.gov (United States)

    Bektas, Oktay

    2015-01-01

    This study investigated pre-service science teachers' pedagogical content knowledge in the physics, chemistry, and biology topics. These topics were the light and sound, the physical and chemical changes, and reproduction, growth, and evolution. Qualitative research design was utilized. Data were collected from 33 pre-service science teachers…

  6. Science Grade 7, Chemistry, Physics, Earth Science, Biology. Curriculum Bulletin, 1968-69 Series, No. 15.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY. Bureau of Curriculum Development.

    This publication is a teacher's guide for teaching seventh grade science in New York City Schools. Activities for four areas -- physics, chemistry, earth science, and biology -- are included. This particular edition is a reprint of Science: Grade 7, Curriculum Bulletin Nos 9a--9d, 1962-1963 Series, which were originally produced in four separate…

  7. Minimum Learning Essentials: Science. Chemistry, Earth Science, Biology, Physics, General Science. Experimental Edition 0/4.

    Science.gov (United States)

    New York City Board of Education, Brooklyn, NY. Div. of Curriculum and Instruction.

    This guide presents the "minimum teaching essentials" published by the New York City Board of Education, for science education in grades 9-12. Covered are: biology, physics, earth science, and chemistry. Work study skills for all subjects are given with content areas, performance objectives, and suggested classroom activities. (APM)

  8. Do Advanced Mathematics Skills Predict Success in Biology and Chemistry Degrees?

    Science.gov (United States)

    Adkins, Michael; Noyes, Andrew

    2018-01-01

    The mathematical preparedness of science undergraduates has been a subject of debate for some time. This paper investigates the relationship between school mathematics attainment and degree outcomes in biology and chemistry across England, a much larger scale of analysis than has hitherto been reported in the literature. A unique dataset which…

  9. Essential Concepts and Underlying Theories from Physics, Chemistry, and Mathematics for "Biochemistry and Molecular Biology" Majors

    Science.gov (United States)

    Wright, Ann; Provost, Joseph; Roecklein-Canfield, Jennifer A.; Bell, Ellis

    2013-01-01

    Over the past two years, through an NSF RCN UBE grant, the ASBMB has held regional workshops for faculty members from around the country. The workshops have focused on developing lists of Core Principles or Foundational Concepts in Biochemistry and Molecular Biology, a list of foundational skills, and foundational concepts from Physics, Chemistry,…

  10. Biodiesel and Integrated STEM: Vertical Alignment of High School Biology/Biochemistry and Chemistry

    Science.gov (United States)

    Burrows, Andrea C.; Breiner, Jonathan M.; Keiner, Jennifer; Behm, Chris

    2014-01-01

    This article explores the vertical alignment of two high school classes, biology and chemistry, around the core concept of biodiesel fuel production. High school teachers and university faculty members investigated biodiesel as it relates to societal impact through a National Science Foundation Research Experience for Teachers. Using an action…

  11. Electron Transfer in Chemistry and Biology-The Primary Events in ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 12. Electron Transfer in Chemistry and Biology – The Primary Events in Photosynthesis. V Krishnan. General Article Volume 2 Issue 12 December 1997 pp 77-86. Fulltext. Click here to view fulltext PDF. Permanent link:

  12. Where Is Earth Science? Mining for Opportunities in Chemistry, Physics, and Biology

    Science.gov (United States)

    Thomas, Julie; Ivey, Toni; Puckette, Jim

    2013-01-01

    The Earth sciences are newly marginalized in K-12 classrooms. With few high schools offering Earth science courses, students' exposure to the Earth sciences relies on the teacher's ability to incorporate Earth science material into a biology, chemistry, or physics course. ''G.E.T. (Geoscience Experiences for Teachers) in the Field'' is an…

  13. Integration of Video-Based Demonstrations to Prepare Students for the Organic Chemistry Laboratory

    Science.gov (United States)

    Nadelson, Louis S.; Scaggs, Jonathan; Sheffield, Colin; McDougal, Owen M.

    2015-01-01

    Consistent, high-quality introductions to organic chemistry laboratory techniques effectively and efficiently support student learning in the organic chemistry laboratory. In this work, we developed and deployed a series of instructional videos to communicate core laboratory techniques and concepts. Using a quasi-experimental design, we tested the…

  14. Using Structure-Based Organic Chemistry Online Tutorials with Automated Correction for Student Practice and Review

    Science.gov (United States)

    O'Sullivan, Timothy P.; Hargaden, Gra´inne C.

    2014-01-01

    This article describes the development and implementation of an open-access organic chemistry question bank for online tutorials and assessments at University College Cork and Dublin Institute of Technology. SOCOT (structure-based organic chemistry online tutorials) may be used to supplement traditional small-group tutorials, thereby allowing…

  15. Evaluation of a Flipped, Large-Enrollment Organic Chemistry Course on Student Attitude and Achievement

    Science.gov (United States)

    Mooring, Suazette R.; Mitchell, Chloe E.; Burrows, Nikita L.

    2016-01-01

    Organic Chemistry is recognized as a course that presents many difficulties and conceptual challenges for students. To combat the high failure rates and poor student attitudes associated with this challenging course, we implemented a "flipped" model for the first-semester, large-enrollment, Organic Chemistry course. In this flipped…

  16. Beyond Rote Learning in Organic Chemistry: The Infusion and Impact of Argumentation in Tertiary Education

    Science.gov (United States)

    Pabuccu, Aybuke; Erduran, Sibel

    2017-01-01

    There exists bias among students that learning organic chemistry topics requires rote learning. In this paper, we address such bias through an organic chemistry activity designed to promote argumentation. We investigated how pre-service science teachers engage in an argumentation about conformational analysis. Analysis of the outcomes concentrated…

  17. Students' Understanding of Alkyl Halide Reactions in Undergraduate Organic Chemistry

    Science.gov (United States)

    Cruz-Ramírez de Arellano, Daniel; Towns, Marcy H.

    2014-01-01

    Organic chemistry is an essential subject for many undergraduate students completing degrees in science, engineering, and pre-professional programs. However, students often struggle with the concepts and skills required to successfully solve organic chemistry exercises. Since alkyl halides are traditionally the first functional group that is…

  18. Student Perceptions of Online Homework Use for Formative Assessment of Learning in Organic Chemistry

    Science.gov (United States)

    Richards-Babb, Michelle; Curtis, Reagan; Georgieva, Zornitsa; Penn, John H.

    2015-01-01

    Use of online homework as a formative assessment tool for organic chemistry coursework was examined. Student perceptions of online homework in terms of (i) its ranking relative to other course aspects, (ii) their learning of organic chemistry, and (iii) whether it improved their study habits and how students used it as a learning tool were…

  19. The Use of Computer-Based Instruction in Undergraduate Organic Chemistry.

    Science.gov (United States)

    Culp, George H.

    Thirty-two computer-based lesson modules in organic chemistry were developed at the University of Texas (Austin) over an 18-month period and evaluated in varying classroom situations for three semesters starting in the Fall of 1972. The modules were designed as supplements to the traditional organic chemistry course of the University. As such,…

  20. Stepwise Approach to Writing Journal-Style Lab Reports in the Organic Chemistry Course Sequence

    Science.gov (United States)

    Wackerly, Jay Wm.

    2018-01-01

    An approach is described that gradually transitions second-year organic chemistry students to writing full "The Journal of Organic Chemistry" ("JOC") style lab reports. The primary goal was to introduce students to and build rhetorical skills in scientific and technical writing. This was accomplished by focusing on four main…

  1. Organic Chemistry and the Native Plants of the Sonoran Desert: Conversion of Jojoba Oil to Biodiesel

    Science.gov (United States)

    Daconta, Lisa V.; Minger, Timothy; Nedelkova, Valentina; Zikopoulos, John N.

    2015-01-01

    A new, general approach to the organic chemistry laboratory is introduced that is based on learning about organic chemistry techniques and research methods by exploring the natural products found in local native plants. As an example of this approach for the Sonoran desert region, the extraction of jojoba oil and its transesterification to…

  2. Introducing Undergraduates to Research Using a Suzuki-Miyaura Cross-Coupling Organic Chemistry Miniproject

    Science.gov (United States)

    Oliveira, Deyvid G. M.; Rosa, Clarissa H.; Vargas, Bruna P.; Rosa, Diego S.; Silveira, Ma´rcia V.; de Moura, Neusa F.; Rosa, Gilber R.

    2015-01-01

    A five-week miniproject is described for an upper-division experimental organic chemistry course. The activities include synthesis of a phenylboronic acid via a Grignard reaction and its use in a Suzuki-Miyaura cross-coupling reaction. Technical skills and concepts normally presented in practical organic chemistry courses are covered, including…

  3. Nonlinear optical polarization analysis in chemistry and biology

    CERN Document Server

    Simpson, Garth J

    2017-01-01

    This rigorous yet accessible guide presents a molecular-based description of nonlinear optical polarization analysis of chemical and biological assemblies. It includes discussion of the most common nonlinear optical microscopy and interfacial measurements used for quantitative analysis, specifically second harmonic generation (SHG), two-photon excited fluorescence (2PEF), vibrational sum frequency generation (SFG), and coherent anti-Stokes Raman spectroscopy/stimulated Raman spectroscopy (CARS/SRS). A linear algebra mathematical framework is developed, allowing step-wise systematic connections to be made between the observable measurements and the molecular response. Effects considered include local field corrections, the molecular orientation distribution, rotations between the molecular frame, the local frame and the laboratory frame, and simplifications from molecular and macromolecular symmetry. Specific examples are provided throughout the book, working from the common and relatively simple case studies ...

  4. Chemistry and biology of terpene trilactones from Ginkgo biloba.

    Science.gov (United States)

    Strømgaard, Kristian; Nakanishi, Koji

    2004-03-19

    Ginkgo biloba, the ginkgo tree, is the oldest living tree, with a long history of use in traditional Chinese medicine. In recent years, the leaf extracts have been widely sold as phytomedicine in Europe and as a dietary supplement worldwide. Effects of Ginkgo biloba extracts have been postulated to include improvement of memory, increased blood circulation, as well as beneficial effects to sufferers of Alzheimer's disease. The most unique components of the extracts are the terpene trilactones, that is, ginkgolides and bilobalide. These structurally complex molecules have been attractive targets for total synthesis. Terpene trilactones are believed to be partly responsible for the neuromodulatory properties of Ginkgo biloba extracts, and several biological effects of the terpene trilactones have been discovered in recent years, making them attractive pharmacological tools that could provide insight into the effects of Ginkgo biloba extracts.

  5. Sunscreen synthesis and their immobilisation on polymethylmethacrylate: an integrated project in organic chemistry, polymer chemistry and photochemistry

    International Nuclear Information System (INIS)

    Murtinho, Dina Maria B.; Serra, Maria Elisa S.; Pineiro, Marta

    2010-01-01

    Dibenzalacetone and other aldol condensation products are known sunscreens commonly used in cosmetics. This type of compounds can easily be prepared in an Organic Chemistry Lab by reaction of aldehydes with ketones in basic medium. These compounds can be incorporated in poly(methyl methacrylate) and used as UV light absorbers, for example in sunglasses. This project has the advantage of using inexpensive reagents which are readily available in Chemistry Laboratories. This experiment can also be a base starting point for discussions of organic, polymer and photochemistry topics. (author)

  6. Using the Cambridge structure database of organic and organometalic compounds in structure biology

    Czech Academy of Sciences Publication Activity Database

    Hašek, Jindřich

    2010-01-01

    Roč. 17, 1a (2010), b24-b26 ISSN 1211-5894. [Discussions in Structural Molecular Biology /8./. Nové Hrady, 18.03.2010-20.03.2010] R&D Projects: GA AV ČR IAA500500701; GA ČR GA305/07/1073 Institutional research plan: CEZ:AV0Z40500505 Keywords : organic chemistry * Cambridge Structure Data base * molecular structure Subject RIV: CD - Macromolecular Chemistry http://xray.cz/ms/bul2010-1a/friday2.pdf

  7. Comparing Recent Organizing Templates for Test Content between ACS Exams in General Chemistry and AP Chemistry

    Science.gov (United States)

    Holme, Thomas

    2014-01-01

    Two different versions of "big ideas" rooted content maps have recently been published for general chemistry. As embodied in the content outline from the College Board, one of these maps is designed to guide curriculum development and testing for advanced placement (AP) chemistry. The Anchoring Concepts Content Map for general chemistry…

  8. Fulminic Acid in the History of Organic Chemistry

    Science.gov (United States)

    Kurzer, Frederick

    2000-07-01

    The story of the discovery, investigation, and eventual correct formulation of fulminic acid, HCNO, extends over a period of 200 years and reflects uniquely, in its many stages, the evolution of organic chemistry from post-alchemistic times to the age of wave mechanics. Fulminic acid was discovered in 1800 when E. Howard serendipitously prepared its highly explosive mercury and silver salts. The determination of its structure presented unusual difficulties and taxed the ingenuity of leading chemists of successive generations. Their work generated a procession of proposed and discarded formulations that was only finally ended in the 1960s with the recognition of fulminic acid as the mesomeric structure and hence with its identification as the parent compound of the important class of the nitrile N-oxides. Recently fulminic acid and several of its isotopomers have been subjected to the most searching spectroscopic investigations and ab initio computations, by which its molecular dimensions and geometry, and its "quasi-linear" structure have been revealed. In technology, mercury fulminate occupied for nearly a century a uniquely important position as the only available practical detonator for every kind of conventional explosive.

  9. A context based approach using Green Chemistry/Bio-remediation principles to enhance interest and learning of organic chemistry in a high school AP chemistry classroom

    Science.gov (United States)

    Miller, Tricia

    The ability of our planet to sustain life and heal itself is not as predictable as it used to be. Our need for educated future scientists who know what our planet needs, and can passionately apply that knowledge to find solutions should be at the heart of science education today. This study of learning organic chemistry through the lens of the environmental problem "What should be done with our food scraps?" explores student interest, and mastery of certain concepts in organic chemistry. This Green Chemistry/ Bio-remediation context-based teaching approach utilizes the Nature MillRTM, which is an indoor food waste composting machine, to learn about organic chemistry, and how this relates to landfill reduction possibilities, and resource production. During this unit students collected food waste from their cafeteria, and used the Nature MillRTM to convert food waste into compost. The use of these hands on activities, and group discussions in a context-based environment enhanced their interest in organic chemistry, and paper chromatography. According to a one-tailed paired T-test, the result show that this context-based approach is a significant way to increase both student interest and mastery of the content.

  10. Aqueous organic chemistry in the atmosphere: sources and chemical processing of organic aerosols.

    Science.gov (United States)

    McNeill, V Faye

    2015-02-03

    Over the past decade, it has become clear that aqueous chemical processes occurring in cloud droplets and wet atmospheric particles are an important source of organic atmospheric particulate matter. Reactions of water-soluble volatile (or semivolatile) organic gases (VOCs or SVOCs) in these aqueous media lead to the formation of highly oxidized organic particulate matter (secondary organic aerosol; SOA) and key tracer species, such as organosulfates. These processes are often driven by a combination of anthropogenic and biogenic emissions, and therefore their accurate representation in models is important for effective air quality management. Despite considerable progress, mechanistic understanding of some key aqueous processes is still lacking, and these pathways are incompletely represented in 3D atmospheric chemistry and air quality models. In this article, the concepts, historical context, and current state of the science of aqueous pathways of SOA formation are discussed.

  11. Chemistry and Biological Activities of Flavonoids: An Overview

    Science.gov (United States)

    Kumar, Shashank; Pandey, Abhay K.

    2013-01-01

    There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production. PMID:24470791

  12. Life as physics and chemistry: A system view of biology.

    Science.gov (United States)

    Baverstock, Keith

    2013-04-01

    Cellular life can be viewed as one of many physical natural systems that extract free energy from their environments in the most efficient way, according to fundamental physical laws, and grow until limited by inherent physical constraints. Thus, it can be inferred that it is the efficiency of this process that natural selection acts upon. The consequent emphasis on metabolism, rather than replication, points to a metabolism-first origin of life with the adoption of DNA template replication as a second stage development. This order of events implies a cellular regulatory system that pre-dates the involvement of DNA and might, therefore, be based on the information acquired as peptides fold into proteins, rather than on genetic regulatory networks. Such an epigenetic cell regulatory model, the independent attractor model, has already been proposed to explain the phenomenon of radiation induced genomic instability. Here it is extended to provide an epigenetic basis for the morphological and functional diversity that evolution has yielded, based on natural selection of the most efficient free energy transduction. Empirical evidence which challenges the current genetic basis of cell and molecular biology and which supports the above proposal is discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Chemistry and Biological Activities of Flavonoids: An Overview

    Directory of Open Access Journals (Sweden)

    Shashank Kumar

    2013-01-01

    Full Text Available There has been increasing interest in the research on flavonoids from plant sources because of their versatile health benefits reported in various epidemiological studies. Since flavonoids are directly associated with human dietary ingredients and health, there is need to evaluate structure and function relationship. The bioavailability, metabolism, and biological activity of flavonoids depend upon the configuration, total number of hydroxyl groups, and substitution of functional groups about their nuclear structure. Fruits and vegetables are the main dietary sources of flavonoids for humans, along with tea and wine. Most recent researches have focused on the health aspects of flavonoids for humans. Many flavonoids are shown to have antioxidative activity, free radical scavenging capacity, coronary heart disease prevention, hepatoprotective, anti-inflammatory, and anticancer activities, while some flavonoids exhibit potential antiviral activities. In plant systems, flavonoids help in combating oxidative stress and act as growth regulators. For pharmaceutical purposes cost-effective bulk production of different types of flavonoids has been made possible with the help of microbial biotechnology. This review highlights the structural features of flavonoids, their beneficial roles in human health, and significance in plants as well as their microbial production.

  14. Students' Understanding of Acids/Bases in Organic Chemistry Contexts

    Science.gov (United States)

    Cartrette, David P.; Mayo, Provi M.

    2011-01-01

    Understanding key foundational principles is vital to learning chemistry across different contexts. One such foundational principle is the acid/base behavior of molecules. In the general chemistry sequence, the Bronsted-Lowry theory is stressed, because it lends itself well to studying equilibrium and kinetics. However, the Lewis theory of…

  15. 2013 Gordon Research Conference on metals in biology and seminar on bioinorganic chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Rosenzweig, Amy C. [Northwestern Univ., Evanston, IL (United States)

    2013-01-25

    Typical topics for lectures and posters include: biochemical and biophysical characterization of new metal containing proteins, enzymes, nucleic acids, factors, and chelators from all forms of life; synthesis, detailed characterization, and reaction chemistry of biomimetic compounds; novel crystal and solution structures of biological molecules and synthetic metal-chelates; discussions of the roles that metals play in medicine, maintenance of the environment, and biogeochemical processes; metal homeostasis; application of theory and computations to the structure and mechanism of metal-containing biological systems; and novel applications of spectroscopy to metals in biological systems.

  16. PSL Chemical Biology Symposia First 2016 Edition: When Chemistry and Biology Share the Language of Discovery.

    Science.gov (United States)

    Gautier, Arnaud; Rodriguez, Raphaël

    2017-05-18

    Chemical biology, the science of understanding biological processes at the molecular level, has grown exponentially with the development of chemical strategies to manipulate and quantify biology with unprecedented precision. Recent advances presented at the Université Paris Sciences et Lettres symposium are discussed. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Recent developments and applications of clickable photoprobes in medicinal chemistry and chemical biology.

    Science.gov (United States)

    Lapinsky, David J; Johnson, Douglas S

    2015-01-01

    Photoaffinity labeling is a well-known biochemical technique that has grown significantly since the turn of the century, principally due to its combination with bioorthogonal/click chemistry reactions. This review highlights new developments and applications of clickable photoprobes in medicinal chemistry and chemical biology. In particular, recent examples of clickable photoprobes for target identification, activity- or affinity-based protein profiling (ABPP or AfBPP), characterization of sterol- or lipid-protein interactions and characterization of ligand-binding sites are presented.

  18. Cross-Course Collaboration in the Undergraduate Chemistry Curriculum: Isotopic Labeling with Sodium Borodeuteride in the Introductory Organic Chemistry Laboratory

    Science.gov (United States)

    Kjonaas, Richard A.; Fitch, Richard W.; Noll, Robert J.

    2017-01-01

    A microscale isotopic labeling experiment is described for the introductory organic chemistry laboratory course wherein half of the students use sodium borohydride (NaBH[subscript 4]) and the other half use sodium borodeuteride (NaBD[subscript 4]) to reduce acetophenone to 1-phenylethanol and then compare spectral data. The cost is reasonable, and…

  19. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT. June through August1963

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1963-10-02

    This report covers the following titles: (1) The Effects of 8-Methyl Lipoic Acid on the Evolution of Oxygen and Reduction of Carbon Dioxide during Photosynthesis; (2) Further {sup 14}C and {sup 15}N Tracer Studies of Amino Acid Synthesis during Photosynthesis by Chlorella Pyrenoidosa; (3) Two-Dimensional High Voltage, Low-Temperature Paper Electrophoresis of {sup 14}C-Labeled Products of Photosynthesis with {sup 14}CO{sub 2}; (4) A Search for Enzymic and Nonenzymic Reactions Between Thiamine Derivatives and Sugar Phosphates; (5) The Cytochrome Content of Purified Spinach Chloroplast Lamellae; (6) The Osmium Tetroxide Fixation of Chloroplast Lamellae; (7) Kinetics of Exoenzymes and Applications to the Determination of the Sequence of Nucleic Acids; (8) Brain Biochemistry and Behavior in Rats; (9) Experiments on Classical Conditioning and Light Habituation in Planarians; (10) Operant Conditioning in Planarians; (11) Manganese Porphyrin Complexes; (12) EPR Studies of Some Complex Organic Solutions; (13) Transient Response of Light-induced Photosynthetic Electron Paramagnetic Resonance Signals: Rhodospirillum rubrum Chromatophores; (14) Studies of the Tautomerism of Amides; (15) Structure and Mechanism of Hydrolysis of the Product of Reaction of PZ05 and Ethyl Ether; (16) A Study of the Irradiation Products of Several Nitrones; (17) Biosynthesis of the Opium Alkaloids; (18) Synthesis of methyl-{beta}-D-thiogalactoside-{sup 35}S; (19) Effect of Acridine Orange and Visible Light on Thymine Dimer Formation and Disruption; (20) Some Aspects of the Radiation Chemistry of DNA; (21) Nuclear Magnetic Resonance; and (22) Studies on the Inhibition of the Photoreduction of FMN.

  20. Organic carbamates in drug design and medicinal chemistry.

    Science.gov (United States)

    Ghosh, Arun K; Brindisi, Margherita

    2015-04-09

    The carbamate group is a key structural motif in many approved drugs and prodrugs. There is an increasing use of carbamates in medicinal chemistry and many derivatives are specifically designed to make drug-target interactions through their carbamate moiety. In this Perspective, we present properties and stabilities of carbamates, reagents and chemical methodologies for the synthesis of carbamates, and recent applications of carbamates in drug design and medicinal chemistry.

  1. Design of SGLT2 Inhibitors for the Treatment of Type 2 Diabetes: A History Driven by Biology to Chemistry.

    Science.gov (United States)

    Cai, Wenqing; Jiang, Linlin; Xie, Yafei; Liu, Yuqiang; Liu, Wei; Zhao, Guilong

    2015-01-01

    A brief history of the design of sodium-dependent glucose cotransporter 2 (SGLT2) inhibitors is reviewed. The design of O-glucoside SGLT2 inhibitors by structural modification of phlorizin, a naturally occurring O-glucoside, in the early stage was a process mainly driven by biology with anticipation of improving SGLT2/SGLT1 selectivity and increasing metabolic stability. Discovery of dapagliflozin, a pioneering C-glucoside SGLT2 inhibitor developed by Bristol-Myers Squibb, represents an important milestone in this history. In the second stage, the design of C-glycoside SGLT2 inhibitors by modifications of the aglycone and glucose moiety of dapagliflozin, an original structural template for almost all C-glycoside SGLT2 inhibitors, was mainly driven by synthetic organic chemistry due to the challenge of designing dapagliflozin derivatives that are patentable, biologically active and synthetically accessible. Structure-activity relationships (SAR) of the SGLT2 inhibitors are also discussed.

  2. Chemistry and biological activity of steroidal glycosides from the Lilium genus.

    Science.gov (United States)

    Munafo, John P; Gianfagna, Thomas J

    2015-03-01

    Plants from the Lilium genus are a rich source of chemical diversity and have been the focus of natural products chemistry research for over twenty years. This manuscript provides a background on the chemistry and nomenclature of steroidal glycosides, as well as a chronological account of the progress between the years of 1989 up to 2014, with respect to their isolation and characterization from the genus. This review highlights the traditional use of lilies, as both food and medicine, and brings attention to the fact that the genus contains 110 accepted species of which the chemistry and biological activity of the steroidal glycosides from the majority have not been investigated to date. Thus, making the genus a relatively untapped resource that contains a potential treasure trove of chemical diversity waiting to be discovered.

  3. A Decade of Click Chemistry in Protein Palmitoylation: Impact on Discovery and New Biology.

    Science.gov (United States)

    Gao, Xinxin; Hannoush, Rami N

    2018-03-15

    Protein palmitoylation plays diverse roles in regulating the trafficking, stability, and activity of cellular proteins. The advent of click chemistry has propelled the field of protein palmitoylation forward by providing specific, sensitive, rapid, and easy-to-handle methods for studying protein palmitoylation. This year marks the 10th anniversary since the first click chemistry-based fatty acid probes for detecting protein lipid modifications were reported. The goal of this review is to highlight key biological advancements in the field of protein palmitoylation during the past 10 years. In particular, we discuss the impact of click chemistry on enabling protein palmitoylation proteomics methods, uncovering novel lipid modifications on proteins and elucidating their functions, as well as the development of non-radioactive biochemical and enzymatic assays. In addition, this review provides context for building and exploring new research avenues in protein palmitoylation through the use of clickable fatty acid probes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Horizons of organic and organoelemental chemistry. 7. All-Russian conference on organometallic chemistry. Program and summaries of communications. V. 1

    International Nuclear Information System (INIS)

    1999-01-01

    Abstracts of the seventh All-Russian conference on organometallic chemistry are presented. The synthesis of organometallic compounds of rare earth, transition elements, the synthesis of organic boron compounds are played an important role in modern organic chemistry and the main part of reports are devoted to these problems. Methods of labelling by radioactive isotopes of organic compounds used in medicine are discussed

  5. On Study of Teaching Reform of Organic Chemistry Course in Applied Chemical Industry Technology

    Science.gov (United States)

    Zhang, Yunshen

    2017-11-01

    with the implementation of new curriculum reform, the education sees great changes in teaching methods. Teaching reform is profound in organic chemistry course in applied chemical industry technology. However, many problems which have never been noticed before occur when reform programs are implemented which harm students’ ability for learning and enthusiasm in side face. This paper proposes reform measures like combining theory and practice, improving professional quality, supplementing professional needs and integrating teaching into life after analyzing organic chemistry course teaching in applied chemical industry technology currently, hoping to play a role of reference for organic chemistry course teaching reform in applied chemical industry technology.

  6. Integrating Chemical Information Instruction into the Chemistry Curriculum on Borrowed Time: A Multiyear Case Study of a Capstone Research Report for Organic Chemistry

    Science.gov (United States)

    Jacobs, Danielle L.; Dalal, Heather A.; Dawson, Patricia H.

    2016-01-01

    To develop information literacy skills in chemistry and biochemistry majors at a primarily undergraduate institution, a multiyear collaboration between chemistry faculty and librarians has resulted in the establishment of a semester-long capstone project for Organic Chemistry II. Information literacy skills were instilled via a progressive…

  7. Recent Advances in the Chemistry and Biology of Naturally Occurring Antibiotics

    Science.gov (United States)

    Chen, Jason S.; Edmonds, David J.; Estrada, Anthony A.

    2009-01-01

    Lead-in Ever since the world-shaping discovery of penicillin, nature’s molecular diversity has been extensively screened for new medications and lead compounds in drug discovery. The search for anti-infective agents intended to combat infectious diseases has been of particular interest and has enjoyed a high degree of success. Indeed, the history of antibiotics is marked with impressive discoveries and drug development stories, the overwhelming majority of which have their origins in nature. Chemistry, and in particular chemical synthesis, has played a major role in bringing naturally occurring antibiotics and their derivatives to the clinic, and no doubt these disciplines will continue to be key enabling technologies for future developments in the field. In this review article, we highlight a number of recent discoveries and advances in the chemistry, biology, and medicine of naturally occurring antibiotics, with particular emphasis on the total synthesis, analog design, and biological evaluation of molecules with novel mechanisms of action. PMID:19130444

  8. Comparable Educational Benefits in Half the Time: An Alternating Organic Chemistry Laboratory Sequence Targeting Prehealth Students

    Science.gov (United States)

    Young, Sherri C.; Colabroy, Keri L.; Baar, Marsha R.

    2016-01-01

    The laboratory is a mainstay in STEM education, promoting the development of critical thinking skills, dexterity, and scientific curiosity. The goals in the laboratory for nonchemistry, prehealth majors, though, could be distinguished from those for chemistry majors. In service courses such as organic chemistry, much laboratory time is often spent…

  9. The Tip of the Iceberg in Organic Chemistry Classes: How Do Students Deal with the Invisible?

    Science.gov (United States)

    Graulich, Nicole

    2015-01-01

    Organic chemistry education is one of the youngest research areas among all chemistry related research efforts, and its published scholarly work has become vibrant and diverse over the last 15 years. Research on problem-solving behavior, students' use of the arrow-pushing formalism, the investigation of students' conceptual knowledge and…

  10. Intuitive Judgments Govern Students' Answering Patterns in Multiple-Choice Exercises in Organic Chemistry

    Science.gov (United States)

    Graulich, Nicole

    2015-01-01

    Research in chemistry education has revealed that students going through their undergraduate and graduate studies in organic chemistry have a fragmented conceptual knowledge of the subject. Rote memorization, rule-based reasoning, and heuristic strategies seem to strongly influence students' performances. There appears to be a gap between what we…

  11. Synthesis and Characterization of Calixarene Tetraethers: An Exercise in Supramolecular Chemistry for the Undergraduate Organic Laboratory

    Science.gov (United States)

    Debbert, Stefan L.; Hoh, Bradley D.; Dulak, David J.

    2016-01-01

    In this experiment for an introductory undergraduate organic chemistry lab, students tetraalkylate tertbutylcalix[4]arene, a bowl-shaped macrocyclic oligophenol, and examine the supramolecular chemistry of the tetraether product by proton nuclear magnetic resonance (NMR) spectroscopy. Complexation with a sodium ion reduces the conformational…

  12. History, biology and chemistry of Mycobacterium ulcerans infections (Buruli ulcer disease).

    Science.gov (United States)

    Chany, Anne-Caroline; Tresse, Cédric; Casarotto, Virginie; Blanchard, Nicolas

    2013-12-01

    Mycobacterium ulcerans infections (Buruli ulcer disease) have a long history that can be traced back 150 years. The successive discoveries of the mycobacteria in 1948 and of mycolactone A/B in 1999, the toxin responsible for this dramatic necrotic skin disease, resulted in a paradigm shift concerning the disease itself and in a broader sense, delineated an entirely new role for bioactive polyketides as virulence factors. The fascinating history, biology and chemistry of M. ulcerans infections are discussed in this review.

  13. Interest in STEM is contagious for students in biology, chemistry, and physics classes

    OpenAIRE

    Hazari, Zahra; Potvin, Geoff; Cribbs, Jennifer D.; Godwin, Allison; Scott, Tyler D.; Klotz, Leidy

    2017-01-01

    We report on a study of the effect of peers? interest in high school biology, chemistry, and physics classes on students? STEM (science, technology, engineering, and mathematics)?related career intentions and course achievement. We define an interest quorum as a science class where students perceive a high level of interest for the subject matter from their classmates. We hypothesized that students who experience such an interest quorum are more likely to choose STEM careers. Using data from ...

  14. Pre-Service Science Teachers’ Pedagogical Content Knowledge in The Physics, Chemistry, and Biology Topics

    OpenAIRE

    Bektas, Oktay

    2015-01-01

    This study investigated pre-service science teachers’ pedagogical content knowledge in the physics, chemistry, and biology topics. These topics were the light and sound, the physical and chemical changes, and reproduction, growth, and evolution. Qualitative research design was utilized. Data were collected from 33 pre-service science teachers (PSTs) by using open-ended questions. Data analysis was performed using descriptive analysis. The results indicated that some PCTs have sufficient infor...

  15. Chemistry and the worm: Caenorhabditis elegans as a platform for integrating chemical and biological research.

    Science.gov (United States)

    Hulme, S Elizabeth; Whitesides, George M

    2011-05-16

    This Review discusses the potential usefulness of the worm Caenorhabditis elegans as a model organism for chemists interested in studying living systems. C. elegans, a 1 mm long roundworm, is a popular model organism in almost all areas of modern biology. The worm has several features that make it attractive for biology: it is small (biology, the Review provides examples of current research with C. elegans that is chemically relevant. It also describes tools-biological, chemical, and physical-that are available to researchers studying the worm. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. An Unprecedented Revolution in Medicinal Chemistry Driven by the Progress of Biological Science.

    Science.gov (United States)

    Chou, Kuo-Chen

    2017-01-01

    The eternal or ultimate goal of medicinal chemistry is to find most effective ways to treat various diseases and extend human beings' life as long as possible. Human being is a biological entity. To realize such an ultimate goal, the inputs or breakthroughs from the advances in biological science are no doubt most important that may even drive medicinal science into a revolution. In this review article, we are to address this from several different angles. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. Designing a 'neotissue' using the principles of biology, chemistry and engineering.

    Science.gov (United States)

    Nannaparaju, Madhusudhan; Oragui, Emeka; Khan, Wasim S

    2012-01-01

    The traditional methods of treating musculoskeletal injuries and disorders are not completely effective and have several limitations. Tissue engineering involves using the principles of biology, chemistry and engineering to design a 'neotissue' that augments a malfunctioning in vivo tissue. The main requirements for functional engineered tissue include reparative cellular components that proliferate on a scaffold grown within a bioreactor that provides specific biochemical and physical signals to regulate cell differentiation and tissue assembly. In this review we provide an overview of the biology of common musculoskeletal tissue and discuss their common pathologies. We also describe the commonly used stem cells, scaffolds and bioreactors and evaluate their role in issue engineering.

  18. Inorganic sulfur-nitrogen compounds: from gunpowder chemistry to the forefront of biological signaling.

    Science.gov (United States)

    Cortese-Krott, Miriam M; Butler, Anthony R; Woollins, J Derek; Feelisch, Martin

    2016-04-14

    The reactions between inorganic sulfur and nitrogen-bearing compounds to form S-N containing species have a long history and, besides assuming importance in industrial synthetic processes, are of relevance to microbial metabolism; waste water treatment; aquatic, soil and atmospheric chemistry; and combustion processes. The recent discovery that hydrogen sulfide and nitric oxide exert often similar, sometimes mutually dependent effects in a variety of biological systems, and that the chemical interaction of these two species leads to formation of S-N compounds brought this chemistry to the attention of physiologists, biochemists and physicians. We here provide a perspective about the potential role of S-N compounds in biological signaling and briefly review their chemical properties and bioactivities in the context of the chronology of their discovery. Studies of the biological role of NO revealed why its chemistry is ideally suited for the tasks Nature has chosen for it; realising how the distinctive properties of sulfur can enrich this bioactivity does much to revive 'die Freude am experimentellen Spiel' of the pioneers in this field.

  19. Potential biological chemistry of hydrogen sulfide (H2S) with the nitrogen oxides.

    Science.gov (United States)

    Bruce King, S

    2013-02-01

    Hydrogen sulfide, an important gaseous signaling agent generated in numerous biological tissues, influences many physiological processes. This biological profile seems reminiscent of nitric oxide, another important endogenously synthesized gaseous signaling molecule. Hydrogen sulfide reacts with nitric oxide or oxidized forms of nitric oxide and nitric oxide donors in vitro to form species that display distinct biology compared to both hydrogen sulfide and NO. The products of these interesting reactions may include small-molecule S-nitrosothiols or nitroxyl, the one-electron-reduced form of nitric oxide. In addition, thionitrous acid or thionitrite, compounds structurally analogous to nitrous acid and nitrite, may constitute a portion of the reaction products. Both the chemistry and the biology of thionitrous acid and thionitrite, compared to nitric oxide or hydrogen sulfide, remain poorly defined. General mechanisms for the formation of S-nitrosothiols, nitroxyl, and thionitrous acid based upon the ability of hydrogen sulfide to act as a nucleophile and a reducing agent with reactive nitric oxide-based intermediates are proposed. Hydrogen sulfide reactivity seems extensive and could have an impact on numerous areas of redox-controlled biology and chemistry, warranting more work in this exciting and developing area. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Coal-related research, organic chemistry, and catalysis

    International Nuclear Information System (INIS)

    Anon.

    1980-01-01

    Coal chemistry research topics included: H exchange at 400 0 C, breaking C-C bonds in coal, molecular weight estimation using small-angle neutron scattering, 13 C NMR spectra of coals, and tunneling during H/D isotope effects. Studies of coal conversion chemistry included thermolysis of bibenzyl and 1-naphthol, heating of coals in phenol, advanced indirect liquefaction based on Koelbel slurry Fischer-Tropsch reactor, and plasma oxidation of coal minerals. Reactions of PAHs in molten SbCl 3 , a hydrocracking catalyst, were studied. Finally, heterogeneous catalysis (desulfurization etc.) was studied using Cu, Au, and Ni surfaces. 7 figures, 6 tables

  1. Measuring Meaningful Learning in the Undergraduate General Chemistry and Organic Chemistry Laboratories: A Longitudinal Study

    Science.gov (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery

    2015-01-01

    Understanding how students learn in the undergraduate chemistry teaching laboratory is an essential component to developing evidence-based laboratory curricula. The Meaningful Learning in the Laboratory Instrument (MLLI) was developed to measure students' cognitive and affective expectations and experiences for learning in the chemistry…

  2. Integration of Computational Chemistry into the Undergraduate Organic Chemistry Laboratory Curriculum

    Science.gov (United States)

    Esselman, Brian J.; Hill, Nicholas J.

    2016-01-01

    Advances in software and hardware have promoted the use of computational chemistry in all branches of chemical research to probe important chemical concepts and to support experimentation. Consequently, it has become imperative that students in the modern undergraduate curriculum become adept at performing simple calculations using computational…

  3. Chemistry

    International Nuclear Information System (INIS)

    Gomez G, H.

    1989-01-01

    A brief description about the development and activities executed in chemistry, in the Instituto de Asuntos Nucleares, during the last years is presented. The plans and feasibility of nuclear techniques in Colombia are also described

  4. Operating experience in correcting severe secondary chemistry upsets by controlling makeup water organics (TOC)

    International Nuclear Information System (INIS)

    Flint, W.G.; Mc Intosh, R.J.

    1986-01-01

    In this paper following observations are presented: conductivity and chloride excursions in steam condensate were directly linked to makeup water quality. Data strongly suggests that the breakdown of makeup water organics was responsible for substandard condensate water quality; although the short-term effects of gross organic contamination have been documented, the longer term consequences of continuous exposure by moderate organic levels needs to be addressed; a greater understanding of the organic removal efficiency of the various water purification technologies is essential to controlling TOC contamination; and a much better understanding of makeup plant chemistry and the interrelationship of makeup water contamination and plant chemistry has proven essential to optimizing plant performance and guaranteeing the best possible steam chemistry. The role of the chemistry group as an active participant in operations has been proven at Kewaunee Nuclear Plant

  5. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ

    Science.gov (United States)

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  6. Improvements to the treatment of organic nitrogen chemistry & deposition in CMAQ

    Science.gov (United States)

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  7. Improvements to the characterization of organic nitrogen chemistry and deposition in CMAQ (CMAS Presentation)

    Science.gov (United States)

    Excess atmospheric nitrogen deposition can cause significant harmful effects to ecosystems. Organic nitrogen deposition can be an important contributor to the total nitrogen budget, contributing 10-30%, however there are large uncertainties in the chemistry and deposition of thes...

  8. Flexible Organic Electronics in Biology: Materials and Devices.

    Science.gov (United States)

    Liao, Caizhi; Zhang, Meng; Yao, Mei Yu; Hua, Tao; Li, Li; Yan, Feng

    2015-12-09

    At the convergence of organic electronics and biology, organic bioelectronics attracts great scientific interest. The potential applications of organic semiconductors to reversibly transmit biological signals or stimulate biological tissues inspires many research groups to explore the use of organic electronics in biological systems. Considering the surfaces of movable living tissues being arbitrarily curved at physiological environments, the flexibility of organic bioelectronic devices is of paramount importance in enabling stable and reliable performances by improving the contact and interaction of the devices with biological systems. Significant advances in flexible organic bio-electronics have been achieved in the areas of flexible organic thin film transistors (OTFTs), polymer electrodes, smart textiles, organic electrochemical ion pumps (OEIPs), ion bipolar junction transistors (IBJTs) and chemiresistors. This review will firstly discuss the materials used in flexible organic bioelectronics, which is followed by an overview on various types of flexible organic bioelectronic devices. The versatility of flexible organic bioelectronics promises a bright future for this emerging area. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. A Simple Physical-Organic Chemistry Experiment A s

    Indian Academy of Sciences (India)

    Note that this rate constant is much larger [4] than the one determined directly by Steenken et al [3] ... The solvolysis reaction can be initiated by making a 100- fold dilution of a solution of the substrate in .... (b) Calvin D Ritchie, Canadian Journal of Chemistry, Vol.64, pp.2239–. 50, 1986. [6] a) John P Richard and William P ...

  10. Beyond Clickers, Next Generation Classroom Response Systems for Organic Chemistry

    Science.gov (United States)

    Shea, Kevin M.

    2016-01-01

    Web-based classroom response systems offer a variety of benefits versus traditional clicker technology. They are simple to use for students and faculty and offer various question types suitable for a broad spectrum of chemistry classes. They facilitate active learning pedagogies like peer instruction and successfully engage students in the…

  11. The 2010 Chemistry Nobel Prize: Pd(0)-Catalyzed Organic Synthesis

    Indian Academy of Sciences (India)

    all the branches of chemistry. The organometallic compounds find application in producing materials needed in many fields of human activity and have helped in vastly improving the quality of life and our life style. The palladium(0) catalyzed cross-coupling reaction is essentially a nucleophilic displacement at a sp2 carbon, ...

  12. Motivational Beliefs and Learning Strategies in Organic Chemistry

    Science.gov (United States)

    Lynch, Douglas Jay; Trujillo, Hernando

    2011-01-01

    Students enter college chemistry courses with different sources of motivation, appropriate or inappropriate assumptions about their probability of success and how to study. This study is theoretically aligned with self-regulated learning research. Clearly, academic performance is closely related to student motivational beliefs and learning…

  13. Molecular Electron Density Theory: A Modern View of Reactivity in Organic Chemistry

    OpenAIRE

    Luis R. Domingo

    2016-01-01

    A new theory for the study of the reactivity in Organic Chemistry, named Molecular Electron Density Theory (MEDT), is proposed herein. MEDT is based on the idea that while the electron density distribution at the ground state is responsible for physical and chemical molecular properties, as proposed by the Density Functional Theory (DFT), the capability for changes in electron density is responsible for molecular reactivity. Within MEDT, the reactivity in Organic Chemistry is studied through ...

  14. Modeling of iodine radiation chemistry in the presence of organic compounds

    International Nuclear Information System (INIS)

    Taghipour, Fariborz; Evans, Greg J.

    2002-01-01

    A kinetic-based model was developed that simulates the radiation chemistry of iodine in the presence of organic compounds. The model's mechanistic description of iodine chemistry and generic semi-mechanistic reactions for various classes of organics, provided a reasonable representation of experimental results. The majority of the model and experimental results of iodine volatilization rates were in agreement within an order of magnitude

  15. Profiles in chemistry: a historical perspective on the national organic symposium.

    Science.gov (United States)

    Fenlon, Edward E; Myers, Brian J

    2013-06-21

    This perspective delineates the history of the National Organic Chemistry Symposium (NOS) and, in doing so, traces the development of organic chemistry over the past 88 years. The NOS is the premier event sponsored by the ACS Division of Organic Chemistry (ORGN) and has been held in odd-numbered years since 1925, with the exceptions of 1943 and 1945. During the 42 symposia, 332 chemists have given 549 plenary lectures. The role the NOS played in the launch of The Journal of Organic Chemistry and Organic Reactions and the initiation of the Roger Adams Award are discussed. Representative examples highlighting the chemistry presented in each era are described, and the evolution of the field is examined by assigning each NOS talk to one of seven subdisciplines and analyzing how the number of talks in each subdiscipline has changed over time. Comparisons of the demographics of speakers, attendees, and ORGN members are made, and superlatives are noted. Personal interest stories of the speakers are discussed, along with the relationships among them, especially their academic lineage. Logistical aspects of the NOS and their historical trends are reviewed. Finally, the human side of science is examined, where over the past century, the NOS has been intertwined with some of the most heated debates in organic chemistry. Conflicts and controversies involving free radicals, reaction mechanisms, and nonclassical carbocations are discussed.

  16. An expert performance approach to examining factors contributing to academic success in organic chemistry

    Science.gov (United States)

    Nandagopal, Kiruthiga

    Successful completion of the introductory course in organic chemistry is a prerequisite for many graduate and professional science programs, yet the failure rate for this course is notoriously high. To date, there have been few studies examining factors contributing to academic success in organic chemistry. This study demonstrates that the online, longitudinal methods used by investigations of expert performance can examine and successfully identify factors contributing to academic success at the college level. Sixty-four students enrolled in introductory organic chemistry during the Fall 2007 and Spring 2008 semesters completed motivation questionnaires, interviews, diaries, and think-aloud reading and problem-solving tasks at three different points across a semester. Measures of spatial ability, general ability, and background preparation were also collected. Each measure was analyzed to determine significant differences between groups differing in grade-point average (GPA) prior to the start of the course and to identify predictors of organic chemistry grade. Variables measuring background preparation, problem-solving strategies and studying strategies were found to be the best predictors of academic success in organic chemistry. Implications for instruction in organic chemistry and effective studying behaviors are discussed.

  17. Problem Types in Synthetic Organic Chemistry Research: Implications for the Development of Curricular Problems for Second-Year Level Organic Chemistry Instruction

    Science.gov (United States)

    Raker, Jeffrey R.; Towns, Marcy H.

    2012-01-01

    Understanding of the nature of science is key to the development of new curricular materials that mirror the practice of science. Three problem types (project level, synthetic planning, and day-to-day) in synthetic organic chemistry emerged during a thematic content analysis of the research experiences of eight practising synthetic organic…

  18. Influence of Biological Macromolecules and Aquatic Chemistries on the Inhibition of Nitrifying Bacteria by Silver Nanoparticles

    Science.gov (United States)

    Radniecki, T. S.; Anderson, J. W.; Schneider, M. C.; Stankus, D. P.; Nason, J. A.; Semprini, L.

    2010-12-01

    The use of silver nanoparticles (Ag-NP) as a broad spectrum biocide in a wide range of consumer goods has grown exponentially since 2006 (1), which may result in an increased release of Ag-NP into wastewater streams and ultimately the receiving bodies of water. Ammonia oxidizing bacteria (AOB) play a critical role in the global nitrogen cycle through the oxidation of ammonia (NH3) to nitrite (NO2-) and are widely considered to be the most sensitive microbial fauna in the environment being readily inhibited by contaminants, including Ag-NP (2). This research used physiological techniques in combination with physical/chemical assays to characterize the inhibition of Nitrosomonas europaea, the model AOB, by silver ions (Ag+), 3-5 nm Ag-NP, 20 nm Ag-NP and 80 nm Ag-NP under a variety of aqueous chemistries. In addition, the stability of Ag-NP suspensions was examined under a variety of aqueous chemistries including in the presences of divalent cations, chloride anions, natural organic matter (NOM), proteins (BSA) and lipopolysaccharides (alginate). Using the stable Ag-NP/test media suspensions, N. europaea was found to be extremely sensitive to Ag+, 3-5 nm Ag-NP, 20 nm Ag-NP and 80 nm Ag-NP with concentrations of 0.1, 0.12, 0.5 and 1.5 ppm, respectively, resulting in a 50% decrease in nitrification rates. The inhibition was correlated with the amount of Ag+ released into solution. It is suspected that the inhibition observed from Ag-NP exposure is caused by the liberated Ag+. The aquatic chemistry of the test media was found to have a profound influence on the stability of Ag-NP suspensions. The presence of Ag ligands (e.g. EDTA and Cl-) reduced toxicity of Ag-NP through the formation of Ag-ligand complexes with the liberated Ag+. The presence of divalent cations (e.g. Ca2+ or Mg2+) resulted in the rapid aggregation of Ag-NP leading to a decrease in Ag+ liberation and thus a decrease in N. europaea inhibition. The presence of 5 ppm NOM resulted in a highly stable Ag

  19. Design of Organic Transformations at Ambient Conditions: Our Sincere Efforts to the Cause of Green Chemistry Practice.

    Science.gov (United States)

    Brahmachari, Goutam

    2016-02-01

    This account summarizes our recent efforts in designing a good number of important organic transformations leading to the synthesis of biologically relevant compounds at room temperature and pressure. Currently, the concept of green chemistry is globally acclaimed and has already advanced quite significantly to emerge as a distinct branch of chemical sciences. Among the principles of green chemistry, one principle is dedicated to the "design of energy efficiency" - that is, to develop synthetic strategies that require less or the minimum amount of energy to carry out a specific reaction with optimum productivity - and the most effective way to save energy is to develop strategies/protocols that are capable enough to carry out the transformations at ambient temperature! As part of on-going developments in green synthetic strategies, the design of reactions under ambient conditions coupled with other green aspects is, thus, an area of current interest. The concept of developing reaction strategies at room temperature and pressure is now an emerging field of research in organic chemistry and is progressing steadily. This account is aimed to offer an overview of our recent research works directly related to this particular field of interest, and highlights the green chemistry practice leading to carbon-carbon and carbon-heteroatom bond-forming reactions of topical significance. Green synthetic routes to a variety of biologically relevant organic molecules (heterocyclic, heteroaromatic, alicyclic, acyclic, etc.) at room temperature and pressure are discussed. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. COSMETICS AS THEMATIC TO APPROACH ORGANIC FUNCTIONS IN CHEMISTRY TEACHING

    OpenAIRE

    FREITAS, Tasielle Lima; DA COSTA, Maria Aparecida; FREITAS, Fabricia Carla Ribeiro Mendes; OLIVEIRA, Tatiana de Fátima; MORAES, Lilian Marciolina; FIELD’S, Karla Amâncio Pinto; REZENDE, Gláucia Aparecida Andrade; SANTOS, Renato Gomes

    2016-01-01

    The science teaching has become more complex each passing day regarding its approach in an attempt to promote a more effective content learning, what requires from the teachers reflection concerning their education teaching, aiming at the use of different teaching strategies, such as the approach of chemistry contents through their relation to a social context in which they are inserted, as the use of cosmetics. This paper reports on a pedagogical intervention project in the subject of Sup...

  1. "Molecules-in-Medicine": Peer-Evaluated Presentations in a Fast-Paced Organic Chemistry Course for Medical Students

    Science.gov (United States)

    Kadnikova, Ekaterina N.

    2013-01-01

    To accentuate the importance of organic chemistry in development of contemporary pharmaceuticals, a three-week unit entitled "Molecules-in-Medicine" was included in the curriculum of a comprehensive one-semester four-credit organic chemistry course. After a lecture on medicinal chemistry concepts and pharmaceutical practices, students…

  2. Effectiveness of Analogy Instructional Strategy on Undergraduate Student's Acquisition of Organic Chemistry Concepts in Mutah University, Jordan

    Science.gov (United States)

    Samara, Nawaf Ahmad Hasan

    2016-01-01

    This study aimed at investigating the effectiveness of analogy instructional strategy on undergraduate students' acquisition of organic chemistry concepts in Mutah University, Jordan. A quasi-experimental design was used in the study; Participants were 97 students who enrolled in organic chemistry course at the department of chemistry during the…

  3. Synthesis and Metalation of a Ligand: An Interdisciplinary Laboratory Experiment for Second-Year Organic and Introductory Inorganic Chemistry Students

    Science.gov (United States)

    Kasting, Benjamin J.; Bowser, Andrew K.; Anderson-Wile, Amelia M.; Wile, Bradley M.

    2015-01-01

    An interdisciplinary laboratory experiment involving second-year undergraduate organic chemistry and introductory inorganic chemistry undergraduate students is described. Organic chemistry students prepare a series of amine-bis(phenols) via a Mannich reaction, and characterize their products using melting point; FTIR; and [superscript 1]H,…

  4. Medicinal and Biological Chemistry (MBC) Library: An Efficient Source of New Hits.

    Science.gov (United States)

    Sebastián-Pérez, Víctor; Roca, Carlos; Awale, Mahendra; Reymond, Jean-Louis; Martinez, Ana; Gil, Carmen; Campillo, Nuria E

    2017-09-25

    Identification of new hits is one of the biggest challenges in drug discovery. Creating a library of well-characterized drug-like compounds is a key step in this process. Our group has developed an in-house chemical library called the Medicinal and Biological Chemistry (MBC) library. This collection has been successfully used to start several medicinal chemistry programs and developed in an accumulation of more than 30 years of experience in drug design and discovery of new drugs for unmet diseases. It contains over 1000 compounds, mainly heterocyclic scaffolds. In this work, analysis of drug-like properties and comparative study with well-known libraries by using different computer software are presented here.

  5. Tracing organizing principles: Learning from the history of systems biology

    DEFF Research Database (Denmark)

    Green, Sara; Wolkenhauer, Olaf

    2014-01-01

    With the emergence of systems biology, the identification of organizing principles is being highlighted as a key research aim. Researchers attempt to “reverse engineer” the functional organization of biological systems using methodologies from mathematics, engineering and computer science while...... taking advantage of data produced by new experimental techniques. While systems biology is a relatively new approach, the quest for general principles of biological organization dates back to systems theoretic approaches in early and mid-twentieth century. The aim of this paper is to draw...... on this historical background in order to increase the understanding of the motivation behind the search for general principles and to clarify different epistemic aims within systems biology. We pinpoint key aspects of earlier approaches that also underlie the current practice. These are i) the focus on relational...

  6. Correlation of preadmission organic chemistry courses and academic performance in biochemistry at a midwest chiropractic doctoral program.

    Science.gov (United States)

    McRae, Marc P

    2010-01-01

    Organic chemistry has been shown to correlate with academic success in the preclinical years of medicine, dentistry, and graduate physiology. The purpose of this study is to examine the relationship between undergraduate organic chemistry grades and first-semester biochemistry grades at a Midwest chiropractic doctoral program. Students enrolled in a first-semester biochemistry course who had completed the prerequisite courses in organic chemistry offered at this same institution were entered into the study. The total grade for each of the three courses was calculated using the midterm and final exam raw scores with a weighting of 50% each. Analysis consisted of obtaining correlation coefficients between the total grades of organic 1 with biochemistry and organic 2 with biochemistry. Using the biochemistry total grade, the students were divided into quartiles and course grades for both organic chemistry 1 and 2 were calculated. For the 109 students in the study, the correlation coefficient between the biochemistry and organic chemistry 1 and biochemistry and organic chemistry 2 courses was r = 0.744 and r = 0.725, respectively. The difference in organic chemistry grades between those in the first and fourth quartiles was 63.2% and 86.9% for organic chemistry 1 (p organic chemistry 2 (p organic chemistry can be used as an indicator of future academic success in a chiropractic biochemistry course. Knowledge of such a relationship could prove useful to identify students who may potentially run into academic difficulty with first-year biochemistry.

  7. [Scientific-Pedagogic School of Biological and Medical Chemistry of the O. O. Bogomolets National Medical University (on the 160th year of its founding)].

    Science.gov (United States)

    Hubs'kyĭ, Iu I; Khmelevs'kyĭ, Iu V; Velykyĭ, M M

    2002-01-01

    In this work the most important stages of the scientific-pedagogic school of biologic and medical chemistry formation in Bogomolets National Medical University starting from the period of foundation as early as in 1863 till nowadays the Chair of Medical Chemistry and Physics as a part of Medical Faculty of Saint Volodymyr Emperor University in the city of Kyiv have been estimated and generalized. The especial attention is attracted to the fact, that it was Kyiv University where firstly the Chair of Biochemistry was created in order of stuyding the regularities of biochemical processes running in the human organism and metabolism disturbances inducing the pathologic processes at some diseases. The scientific and scientific-pedagogical trends of the chair work in different periods of its development are presented, simltneously the leading role of famous Ukrainian scientists--biochemicians in foundation and development of biologic and medical chemistry scientific school in the University are emphasized. Nowadays the Chair is the educational and scientific center supporting and developing the best traditions on training the specialists of different qualification levels: physicians Masters of Science, Philosophy Doctors and Doctors of Science in Medicine and Biology. The Chair is considered to be a basic one among the Ukraine higher medic and pharmaceutic educational institutions having the III-IV accreditation rate on the problems of teaching-organizational, educational-methodical and scientific work. On the Chair base there is functioning the Scientific Problem-Solving Commission of Ministry of health Protections of Academy of Medical Sciences of Ukraine "Biological and medical Chemistry" (the chairman is the Corresponding-Member of Academy of Medical Sciences of Ukraine, Prof. Yu.I. Gubsky. The Chair personnel compiled and issued the contemporary manuals in Ukraine language on Biologic and Bioorganic Chemistry.

  8. Dovetailing biology and chemistry: integrating the Gene Ontology with the ChEBI chemical ontology

    Science.gov (United States)

    2013-01-01

    Background The Gene Ontology (GO) facilitates the description of the action of gene products in a biological context. Many GO terms refer to chemical entities that participate in biological processes. To facilitate accurate and consistent systems-wide biological representation, it is necessary to integrate the chemical view of these entities with the biological view of GO functions and processes. We describe a collaborative effort between the GO and the Chemical Entities of Biological Interest (ChEBI) ontology developers to ensure that the representation of chemicals in the GO is both internally consistent and in alignment with the chemical expertise captured in ChEBI. Results We have examined and integrated the ChEBI structural hierarchy into the GO resource through computationally-assisted manual curation of both GO and ChEBI. Our work has resulted in the creation of computable definitions of GO terms that contain fully defined semantic relationships to corresponding chemical terms in ChEBI. Conclusions The set of logical definitions using both the GO and ChEBI has already been used to automate aspects of GO development and has the potential to allow the integration of data across the domains of biology and chemistry. These logical definitions are available as an extended version of the ontology from http://purl.obolibrary.org/obo/go/extensions/go-plus.owl. PMID:23895341

  9. Dovetailing biology and chemistry: integrating the Gene Ontology with the ChEBI chemical ontology.

    Science.gov (United States)

    Hill, David P; Adams, Nico; Bada, Mike; Batchelor, Colin; Berardini, Tanya Z; Dietze, Heiko; Drabkin, Harold J; Ennis, Marcus; Foulger, Rebecca E; Harris, Midori A; Hastings, Janna; Kale, Namrata S; de Matos, Paula; Mungall, Christopher J; Owen, Gareth; Roncaglia, Paola; Steinbeck, Christoph; Turner, Steve; Lomax, Jane

    2013-07-29

    The Gene Ontology (GO) facilitates the description of the action of gene products in a biological context. Many GO terms refer to chemical entities that participate in biological processes. To facilitate accurate and consistent systems-wide biological representation, it is necessary to integrate the chemical view of these entities with the biological view of GO functions and processes. We describe a collaborative effort between the GO and the Chemical Entities of Biological Interest (ChEBI) ontology developers to ensure that the representation of chemicals in the GO is both internally consistent and in alignment with the chemical expertise captured in ChEBI. We have examined and integrated the ChEBI structural hierarchy into the GO resource through computationally-assisted manual curation of both GO and ChEBI. Our work has resulted in the creation of computable definitions of GO terms that contain fully defined semantic relationships to corresponding chemical terms in ChEBI. The set of logical definitions using both the GO and ChEBI has already been used to automate aspects of GO development and has the potential to allow the integration of data across the domains of biology and chemistry. These logical definitions are available as an extended version of the ontology from http://purl.obolibrary.org/obo/go/extensions/go-plus.owl.

  10. USE OF GRAPHIC ORGANIZERS IN SECONDARY CHEMISTRY LESSONS

    OpenAIRE

    Nakiboglu, Canan

    2017-01-01

    Graphicorganizers are the visual representations that show the organization orstructure of concepts as well as relationships between concepts. The effectiveuse of graphic organizers may be a magnificent strategy to help studentsconnect ideas and they can be added to instructional materials to communicatethe logical structure of the instructional material. This study aims to showhow graphic organizer use within teaching duration by presenting differenttypes of graphic organizers and to provide...

  11. Macromolecular crowding: chemistry and physics meet biology (Ascona, Switzerland, 10-14 June 2012).

    Science.gov (United States)

    Foffi, G; Pastore, A; Piazza, F; Temussi, P A

    2013-08-02

    conference held in Ascona from 10 to 14 June 2012. In the unique scenario of the Maggiore lake and absorbed in the magic atmosphere of the Centro Stefano Franscini (CSF) at Monte Verità, we enjoyed three-and-a-half days of intense and inspiring activity, where not only many of the most prominent scientists working on macromolecular crowding, but also experts in closely related fields such as colloids and soft matter presented their work. The meeting was intended and has been organized to bring theoreticians and experimentalists together in the attempt to promote an active dialogue. Moreover, we wanted different disciplines to be represented, notably physics and chemistry, besides biology, as cross-fertilization is proving an increasingly fundamental source of inspiration and advancement. This issue of Physical Biology (PB) features a selection of the oral contributions presented at the conference, expanded in the form of research or review articles. PB, one of the scientific journals of the Institute of Physics (IOP), is one of the most dynamic and lively forums active at the interface between biology on one side, and physics and mathematics on the other. As its mission is stated by IOP, PB 'focuses on research in which physics-based approaches lead to new insights into biological systems at all scales of space and time, and all levels of complexity'. For these reasons, and also in view of its high reputation and broad readership, PB appears to be the ideal place for disseminating the thriving pieces of research presented at the conference. We are extremely grateful to PB and its kind and efficient editorial staff who helped make this issue a great scientific follow-up to the conference. The opening lecture of the conference, the first of four day-opening keynote lectures, was given by Allen P Minton from NIH (USA), possibly the most influential among the pioneers in the field. He provided a lucid and well-thought-out overview of the concept of macromolecular crowding

  12. Macromolecular crowding: chemistry and physics meet biology (Ascona, Switzerland, 10-14 June 2012)

    Science.gov (United States)

    Foffi, G.; Pastore, A.; Piazza, F.; Temussi, P. A.

    2013-08-01

    held in Ascona from 10 to 14 June 2012. In the unique scenario of the Maggiore lake and absorbed in the magic atmosphere of the Centro Stefano Franscini (CSF) at Monte Verità, we enjoyed three-and-a-half days of intense and inspiring activity, where not only many of the most prominent scientists working on macromolecular crowding, but also experts in closely related fields such as colloids and soft matter presented their work. The meeting was intended and has been organized to bring theoreticians and experimentalists together in the attempt to promote an active dialogue. Moreover, we wanted different disciplines to be represented, notably physics and chemistry, besides biology, as cross-fertilization is proving an increasingly fundamental source of inspiration and advancement. This issue of Physical Biology (PB) features a selection of the oral contributions presented at the conference, expanded in the form of research or review articles. PB, one of the scientific journals of the Institute of Physics (IOP), is one of the most dynamic and lively forums active at the interface between biology on one side, and physics and mathematics on the other. As its mission is stated by IOP, PB 'focuses on research in which physics-based approaches lead to new insights into biological systems at all scales of space and time, and all levels of complexity'. For these reasons, and also in view of its high reputation and broad readership, PB appears to be the ideal place for disseminating the thriving pieces of research presented at the conference. We are extremely grateful to PB and its kind and efficient editorial staff who helped make this issue a great scientific follow-up to the conference. The opening lecture of the conference, the first of four day-opening keynote lectures, was given by Allen P Minton from NIH (USA), possibly the most influential among the pioneers in the field. He provided a lucid and well-thought-out overview of the concept of macromolecular crowding through an

  13. Chemistry

    International Nuclear Information System (INIS)

    Ferris, L.M.

    1975-01-01

    The chemical research and development efforts related to the design and ultimate operation of molten-salt breeder reactor systems are concentrated on fuel- and coolant-salt chemistry, including the development of analytical methods for use in these systems. The chemistry of tellurium in fuel salt is being studied to help elucidate the role of this element in the intergranular cracking of Hastelloy N. Studies were continued of the effect of oxygen-containing species on the equilibrium between dissolved UF 3 and dissolved UF 4 , and, in some cases, between the dissolved uranium fluorides and graphite, and the UC 2 . Several aspects of coolant-salt chemistry are under investigation. Hydroxy and oxy compounds that could be formed in molten NaBF 4 are being synthesized and characterized. Studies of the chemistry of chromium (III) compounds in fluoroborate melts were continued as part of a systematic investigation of the corrosion of structural alloys by coolant salt. An in-line voltammetric method for determining U 4+ /U 3+ ratios in fuel salt was tested in a forced-convection loop over a six-month period. (LK)

  14. Chemistry and Biology of HPAs: A Family of Ceramide Trafficking Inhibitors.

    Science.gov (United States)

    Berkeš, Dušan; Daïch, Adam; Santos, Cécile; Ballereau, Stéphanie; Génisson, Yves

    2016-12-05

    In 2001, two years before the disclosure of the CERT-associated Cer transfer machinery, N-(3-hydroxy-1-hydroxymethyl-3-phenylpropyl)alkanamides (HPAs) were described as the first, and to date unique, family of intracellular Cer trafficking inhibitors. The dodecanamide derivative, HPA-12, turned out to be a benchmark as a cellular inhibitor of CERT-mediated de novo sphingomyelin biosynthesis. In only 15 years after its first disclosure, this compound has prompted a growing number of biological and chemical studies. Its initial chemical development closely paralleled the study of the CERT protein. It was only after its structural revision in 2011 that HPA-12 received broad attention from the synthetic chemistry community, leading to novel analogues with enhanced protein binding. This Minireview aims at presenting an exhaustive report of the syntheses of HPA-12 and analogues. Biological activities of this CERT inhibitor and structure-activity relationships are also presented to afford a comprehensive overview of the chemistry and biology of the HPA series. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Connecting synthetic chemistry decisions to cell and genome biology using small-molecule phenotypic profiling.

    Science.gov (United States)

    Wagner, Bridget K; Clemons, Paul A

    2009-12-01

    Discovering small-molecule modulators for thousands of gene products requires multiple stages of biological testing, specificity evaluation, and chemical optimization. Many cellular profiling methods, including cellular sensitivity, gene expression, and cellular imaging, have emerged as methods to assess the functional consequences of biological perturbations. Cellular profiling methods applied to small-molecule science provide opportunities to use complex phenotypic information to prioritize and optimize small-molecule structures simultaneously against multiple biological endpoints. As throughput increases and cost decreases for such technologies, we see an emerging paradigm of using more information earlier in probe-discovery and drug-discovery efforts. Moreover, increasing access to public datasets makes possible the construction of 'virtual' profiles of small-molecule performance, even when multiplexed measurements were not performed or when multidimensional profiling was not the original intent. We review some key conceptual advances in small-molecule phenotypic profiling, emphasizing connections to other information, such as protein-binding measurements, genetic perturbations, and cell states. We argue that to maximally leverage these measurements in probe-discovery and drug-discovery requires a fundamental connection to synthetic chemistry, allowing the consequences of synthetic decisions to be described in terms of changes in small-molecule profiles. Mining such data in the context of chemical structure and synthesis strategies can inform decisions about chemistry procurement and library development, leading to optimal small-molecule screening collections.

  16. On the Applicability of the Green Chemistry Principles to Sustainability of Organic Matter on Asteroids

    Directory of Open Access Journals (Sweden)

    Vera M. Kolb

    2010-06-01

    Full Text Available The connection between astrobiology and green chemistry represents a new approach to sustainability of organic matter on asteroids or similar bodies. Green chemistry is chemistry which is environmentally friendly. One obvious way for chemistry to be green is to use water as a solvent, instead of more toxic organic solvents. Many astrobiological reactions occur in the aqueous medium, for example in the prebiotic soup or during the aqueous alteration period on asteroids. Thus any advances in the green organic reactions in water are directly applicable to astrobiology. Another green chemistry approach is to abolish use of toxic solvents. This can be accomplished by carrying out the reactions without a solvent in the solventless or solid-state reactions. The advances in these green reactions are directly applicable to the chemistry on asteroids during the periods when water was not available. Many reactions on asteroids may have been done in the solid mixtures. These reactions may be responsible for a myriad of organic compounds that have been isolated from the meteorites.

  17. Perception of the Relevance of Organic Chemistry in a German Pharmacy Students’ Course

    Science.gov (United States)

    Wehle, Sarah

    2016-01-01

    Objective. To investigate German pharmacy students’ attitudes toward the relevance of organic chemistry training in Julius Maximilian University (JMU) of Würzburg with regard to subsequent courses in the curricula and in later prospective career options. Methods. Surveys were conducted in the second-year organic chemistry course (50 participants) as well as during the third-year and fourth-year lecture cycle on medicinal and pharmaceutical chemistry (66 participants) in 2014. Results. Students’ attitudes were surprisingly consistent throughout the progress of the degree course. Students considered organic chemistry very relevant to the pharmacy study program (95% junior and 97% senior students), and of importance for their future pharmacy program (88% junior and 94% senior students). With regard to prospective career options, the perceived relevance was considerably lower and attitudes were less homogenous. Conclusions. German pharmacy students at JMU Würzburg consider organic chemistry of high relevance for medicinal chemistry and other courses in JMU’s pharmacy program. PMID:27170811

  18. A study of how precursor key concepts for organic chemistry success are understood by general chemistry students

    Science.gov (United States)

    Meyer, Patrick Gerard

    This study examines college student understanding of key concepts that will support future organic chemistry success as determined by university instructors. During four one-hour individual interviews the sixteen subjects attempted to solve general chemistry problems. A think-aloud protocol was used along with a whiteboard where the students could draw and illustrate their ideas. The protocols for the interviews were adapted from the Covalent Structure and Bonding two-tiered multiple choice diagnostic instrument (Peterson, Treagust, & Garnett, 1989) and augmented by the Geometry and Polarity of Molecules single-tiered multiple choice instrument (Furio & Calatayud, 1996). The interviews were videotaped, transcribed, and coded for analysis to determine the subjects' understanding of the key ideas. The subjects displayed many misconceptions that were summarized into nine assertions about student conceptualization of chemistry. (1) Many students misunderstand the location and nature of intermolecular forces. (2) Some think electronegativity differences among atoms in a molecule are sufficient to make the molecule polar, regardless of spatial arrangement. (3) Most know that higher phase change temperatures imply stronger intermolecular attractions, but many do not understand the difference between covalent molecular and covalent network substances. (4) Many have difficulty deciding whether a molecule is polar or non-polar, often confusing bilateral symmetry with spatial symmetry in all three dimensions. (5) Many cannot reliably draw correct Lewis structures due to carelessness and overuse of flawed algorithms. (6) Many are confused by how electrons can both repel one other and facilitate bonding between atoms via orbitals---this seems oxymoronic to them. (7) Many cannot explain why the atoms of certain elements do not follow the octet rule and some believe the octet rule alone can determine the shape of a molecule. (8) Most do know that electronegativity and polarity

  19. Synthesis of Organic Matter of Prebiotic Chemistry at the Protoplanetary Disc

    Science.gov (United States)

    Snytnikov, Valeriy; Stoynovskaya, Olga; Rudina, Nina

    We have carried out scanning electron microscopic examination of CM carbonaceous chondrites meteorites Migey, Murchison, Staroe Boriskino aged more than 4.56 billion years (about 50 million years from the beginning of the formation of the Solar system). Our study confirmed the conclusion of Rozanov, Hoover and other researchers about the presence of microfossils of bacterial origin in the matrix of all these meteorites. Since the time of the Solar system formation is 60 - 100 million years, the primary biocenosis emerged in the protoplanetary disc of the Solar system before meteorites or simultaneously with them. It means that prebiological processes and RNA world appeared even earlier in the circumsolar protoplanetary disc. Most likely, this appearance of prebiotic chemistry takes place nowday in massive and medium-massive discs of the observed young stellar objects (YSO) class 0 and I. The timescale of the transition from chemical to biological evolution took less than 50 million years for the Solar system. Further evolution of individual biocenosis in a protoplanetary disc associated with varying physico-chemical conditions during the formation of the Solar system bodies. Biocenosis on these bodies could remove or develop under the influence of many cosmic factors and geological processes in the case of Earth. To complete the primary biosphere formation in short evolution time - millions of years - requires highly efficient chemical syntheses. In industrial chemistry for the efficient synthesis of ammonia, hydrogen cyanide, methanol and other organic species, that are the precursors to obtain prebiotic compounds, catalytic reactors of high pressure are used. Thus (1) necessary amount of the proper catalyst in (2) high pressure areas of the disc can trigger these intense syntheses. The disc contains the solids with the size from nanoparticle to pebble. Iron and magnesium is catalytically active ingredient for such solids. The puzzle is a way to provide hydrogen

  20. N-acylsulfonamides: Synthetic routes and biological potential in medicinal chemistry.

    Science.gov (United States)

    Ammazzalorso, Alessandra; De Filippis, Barbara; Giampietro, Letizia; Amoroso, Rosa

    2017-12-01

    Sulfonamide is a common structural motif in naturally occurring and synthetic medicinal compounds. The rising interest in sulfonamides and N-acyl derivatives is attested by the large number of drugs and lead compounds identified in last years, explored in different fields of medicinal chemistry and showing biological activity. Many acylsulfonamide derivatives were designed and synthesized as isosteres of carboxylic acids, being the characteristics of these functional groups very close. Starting from chemical routes to N-acylsulfonamides, this review explores compounds of pharmaceutical interest, developed as enzymatic inhibitors or targeting receptors. © 2017 John Wiley & Sons A/S.

  1. The chemistry-biology-medicine continuum and the drug discovery and development process in academia.

    Science.gov (United States)

    Nicolaou, K C

    2014-09-18

    Admirable as it is, the drug discovery and development process is continuously undergoing changes and adjustments in search of further improvements in efficiency, productivity, and profitability. Recent trends in academic-industrial partnerships promise to provide new opportunities for advancements of this process through transdisciplinary collaborations along the entire spectrum of activities involved in this complex process. This perspective discusses ways to promote the emerging academic paradigm of the chemistry-biology-medicine continuum as a means to advance the drug discovery and development process. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Advances in metabolome information retrieval: turning chemistry into biology. Part II: biological information recovery.

    Science.gov (United States)

    Tebani, Abdellah; Afonso, Carlos; Bekri, Soumeya

    2017-08-25

    This work reports the second part of a review intending to give the state of the art of major metabolic phenotyping strategies. It particularly deals with inherent advantages and limits regarding data analysis issues and biological information retrieval tools along with translational challenges. This Part starts with introducing the main data preprocessing strategies of the different metabolomics data. Then, it describes the main data analysis techniques including univariate and multivariate aspects. It also addresses the challenges related to metabolite annotation and characterization. Finally, functional analysis including pathway and network strategies are discussed. The last section of this review is devoted to practical considerations and current challenges and pathways to bring metabolomics into clinical environments.

  3. Spectroscopy 101: A Practical Introduction to Spectroscopy and Analysis for Undergraduate Organic Chemistry Laboratories

    Science.gov (United States)

    Morrill, Lucas A.; Kammeyer, Jacquelin K.; Garg, Neil K.

    2017-01-01

    An undergraduate organic chemistry laboratory that provides an introduction to various spectroscopic techniques is reported. Whereas organic spectroscopy is most often learned and practiced in the context of reaction analyses, this laboratory experiment allows students to become comfortable with [superscript 1]H NMR, [superscript 13]C NMR, and IR…

  4. An Undergraduate Organic Chemistry Laboratory: The Facile Hydrogenation of Methyl Trans-Cinnamate

    Science.gov (United States)

    O'Connor, Kenneth J.; Zuspan, Kimberly; Berry, Lonnie

    2011-01-01

    Hydrogenation of alkenes is an important reaction in the synthesis of organic molecules. In this experiment, students conduct a high-yield microscale hydrogenation reaction of methyl "trans"-cinnamate using a readily available, safe, and convenient hydrogen source. The conditions are similar to those seen in an organic chemistry textbook for an…

  5. A Cost-Effective Two-Part Experiment for Teaching Introductory Organic Chemistry Techniques

    Science.gov (United States)

    Sadek, Christopher M.; Brown, Brenna A.; Wan, Hayley

    2011-01-01

    This two-part laboratory experiment is designed to be a cost-effective method for teaching basic organic laboratory techniques (recrystallization, thin-layer chromatography, column chromatography, vacuum filtration, and melting point determination) to large classes of introductory organic chemistry students. Students are exposed to different…

  6. Acid-Base Learning Outcomes for Students in an Introductory Organic Chemistry Course

    Science.gov (United States)

    Stoyanovich, Carlee; Gandhi, Aneri; Flynn, Alison B.

    2015-01-01

    An outcome-based approach to teaching and learning focuses on what the student demonstrably knows and can do after instruction, rather than on what the instructor teaches. This outcome-focused approach can then guide the alignment of teaching strategies, learning activities, and assessment. In organic chemistry, mastery of organic acid-base…

  7. A Simple Physical-Organic Chemistry Experiment A s

    Indian Academy of Sciences (India)

    A very important intermediate in many organic reactions is the carbocation. As the name implies, carbocation is an organic cation containing a positively charged carbon. It has only a sextet of electrons surrounding the charged carbon and is therefore quite reactive. Originally they were called carbonium ions. The parent.

  8. Analytical Chemistry Laboratory (ACL) procedure compendium. Volume 4, Organic methods

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    This interim notice covers the following: extractable organic halides in solids, total organic halides, analysis by gas chromatography/Fourier transform-infrared spectroscopy, hexadecane extracts for volatile organic compounds, GC/MS analysis of VOCs, GC/MS analysis of methanol extracts of cryogenic vapor samples, screening of semivolatile organic extracts, GPC cleanup for semivolatiles, sample preparation for GC/MS for semi-VOCs, analysis for pesticides/PCBs by GC with electron capture detection, sample preparation for pesticides/PCBs in water and soil sediment, report preparation, Florisil column cleanup for pesticide/PCBs, silica gel and acid-base partition cleanup of samples for semi-VOCs, concentrate acid wash cleanup, carbon determination in solids using Coulometrics` CO{sub 2} coulometer, determination of total carbon/total organic carbon/total inorganic carbon in radioactive liquids/soils/sludges by hot persulfate method, analysis of solids for carbonates using Coulometrics` Model 5011 coulometer, and soxhlet extraction.

  9. Review of the genus Ipomoea: traditional uses, chemistry and biological activities

    Directory of Open Access Journals (Sweden)

    Marilena Meira

    Full Text Available Approximately 600-700 species of Ipomoea, Convolvulaceae, are found throughout tropical and subtropical regions of the world. Several of those species have been used as ornamental plants, food, medicines or in religious ritual. The present work reviews the traditional uses, chemistry and biological activities of Ipomoea species and illustrates the potential of the genus as a source of therapeutic agents. These species are used in different parts of the world for the treatment of several diseases, such as, diabetes, hypertension, dysentery, constipation, fatigue, arthritis, rheumatism, hydrocephaly, meningitis, kidney ailments and inflammations. Some of these species showed antimicrobial, analgesic, spasmolitic, spasmogenic, hypoglycemic, hypotensive, anticoagulant, anti-inflammatory, psychotomimetic and anticancer activities. Alkaloids, phenolics compounds and glycolipids are the most common biologically active constituents from these plant extracts.

  10. [Research progress and trend analysis of biology and chemistry of Taxus medicinal resources].

    Science.gov (United States)

    Hao, Da-Cheng; Xiao, Pei-Gen; Peng, Yong; Liu, Ming; Huo, Li

    2012-07-01

    Taxus is the source plant of anti-cancer drug paclitaxel and its biosynthetic precursor, analogs and derivatives, which has been studying for decades. There are many endemic Taxus species in China, which have been studied in the field of multiple disciplines. Based on the recent studies of the researchers, this review comments on the study of Taxus biology and chemistry. The bibliometric method is used to quantify the global scientific production of Taxus-related research, and identify patterns and tendencies of Taxus-related articles. Gaps are present in knowledge about the genomics, epigenomics, transcriptomics, proteomics, metabolomics and bioinformatics of Taxus and their endophytic fungi. Systems biology and various omics technologies will play an increasingly important role in the coming decades.

  11. Research Data in Core Journals in Biology, Chemistry, Mathematics, and Physics.

    Science.gov (United States)

    Womack, Ryan P

    2015-01-01

    This study takes a stratified random sample of articles published in 2014 from the top 10 journals in the disciplines of biology, chemistry, mathematics, and physics, as ranked by impact factor. Sampled articles were examined for their reporting of original data or reuse of prior data, and were coded for whether the data was publicly shared or otherwise made available to readers. Other characteristics such as the sharing of software code used for analysis and use of data citation and DOIs for data were examined. The study finds that data sharing practices are still relatively rare in these disciplines' top journals, but that the disciplines have markedly different practices. Biology top journals share original data at the highest rate, and physics top journals share at the lowest rate. Overall, the study finds that within the top journals, only 13% of articles with original data published in 2014 make the data available to others.

  12. Molecular mechanism of acrylamide neurotoxicity: lessons learned from organic chemistry.

    Science.gov (United States)

    LoPachin, Richard M; Gavin, Terrence

    2012-12-01

    Acrylamide (ACR) produces cumulative neurotoxicity in exposed humans and laboratory animals through a direct inhibitory effect on presynaptic function. In this review, we delineate how knowledge of chemistry provided an unprecedented understanding of the ACR neurotoxic mechanism. We also show how application of the hard and soft, acids and bases (HSAB) theory led to the recognition that the α,β-unsaturated carbonyl structure of ACR is a soft electrophile that preferentially forms covalent bonds with soft nucleophiles. In vivo proteomic and in chemico studies demonstrated that ACR formed covalent adducts with highly nucleophilic cysteine thiolate groups located within active sites of presynaptic proteins. Additional research showed that resulting protein inactivation disrupted nerve terminal processes and impaired neurotransmission. ACR is a type-2 alkene, a chemical class that includes structurally related electrophilic environmental pollutants (e.g., acrolein) and endogenous mediators of cellular oxidative stress (e.g., 4-hydroxy-2-nonenal). Members of this chemical family produce toxicity via a common molecular mechanism. Although individual environmental concentrations might not be toxicologically relevant, exposure to an ambient mixture of type-2 alkene pollutants could pose a significant risk to human health. Furthermore, environmentally derived type-2 alkenes might act synergistically with endogenously generated unsaturated aldehydes to amplify cellular damage and thereby accelerate human disease/injury processes that involve oxidative stress. These possibilities have substantial implications for environmental risk assessment and were realized through an understanding of ACR adduct chemistry. The approach delineated here can be broadly applied because many toxicants of different chemical classes are electrophiles that produce toxicity by interacting with cellular proteins.

  13. FOREWORD: Third Nordic Symposium on Computer Simulation in Physics, Chemistry, Biology and Mathematics

    Science.gov (United States)

    Kaski, K.; Salomaa, M.

    1990-01-01

    ), physics (fluid-dynamical and quantum-mechanical calculations; extensive numerical simulations of various condensed-matter systems; the development of stellar constellations, even the early Universe), chemistry (quantum-chemical calculations on the structures of new chemical compounds; chemical reactions and reaction dynamics), and biology (various models, for example, in population dynamics). We succeeded in our effort to assemble several internationally recognized researchers of Computational Science to deliver invited talks on a couple of exceptionally beautiful late-summer days in the modern premises of the Adult Education Center at Lahti. Among the plenary speakers, Per Bak described his highly original work on self-organized criticality. David Ceperley discussed pioneering numerical simulations of superfluid helium in which, for the first time, Feynman's path-integral formulation of quantum mechanics has been implemented on a computer. Jim Gunton presented his comprehensive studies of the Cahn-Hilliard equation for the dynamics of ordering in a condensed-matter system far from equilibrium, while Alex Hansen explained those on nonlinear breakdown in disordered materials. Representing the important field of computational chemistry, Bo Jönsson dealt with attractive forces between polyelectrolytes. Kurt Kremer gave an interesting account on computer-simulation studies of complex polymer systems, while Ole Mouritsen reviewed studies of interfacial fluctuations in lipid membranes. Pekka Pyykkö introduced his pioneering work which has led to predictions of completely novel chemical species. Annette Zippelius gave an expert introduction to the highly active field of neural networks. It is evident from each of these intriguing plenary contributions that, indeed, the computational approach is a frontier field of science, possibly providing the most versatile research method available today. We also arranged a competition for the best Posters presented at the Symposium; the

  14. Secondary metabolites from the South China Sea invertebrates: chemistry and biological activity.

    Science.gov (United States)

    Zhang, Wen; Guo, Yue-Wei; Gu, Yucheng

    2006-01-01

    The increasing demand for new lead compounds in the pharmaceutical and agrochemical industries has driven scientists to search for new sources of bioactive natural products. Marine invertebrates are a rich source of novel, bioactive secondary metabolites and they have attracted a great deal of attention from scientists in the fields of chemistry, pharmacology, ecology, and molecular biology. During the past 25 years, many complex and structurally unique secondary metabolites have been isolated from the invertebrates inhabiting the South China Sea. These metabolites are responsible for various bioactivities such as anti-tumor, anti-inflammation and antioxidant activities, and/or they act on the cardiovascular system. This review will focus on the marine natural product chemistry of invertebrates from the South China Sea, aiming to give the reader a brief view of the compounds isolated from these invertebrates, as well as their biological activities. The article covers the literature published during the period from the beginning of 1980 to the end of 2005, with 340 citations and 811 compounds from invertebrates from the South China Sea, including sponges, coelenterates, molluscs and echinoderms.

  15. Interest in STEM is contagious for students in biology, chemistry, and physics classes

    Science.gov (United States)

    Hazari, Zahra; Potvin, Geoff; Cribbs, Jennifer D.; Godwin, Allison; Scott, Tyler D.; Klotz, Leidy

    2017-01-01

    We report on a study of the effect of peers’ interest in high school biology, chemistry, and physics classes on students’ STEM (science, technology, engineering, and mathematics)–related career intentions and course achievement. We define an interest quorum as a science class where students perceive a high level of interest for the subject matter from their classmates. We hypothesized that students who experience such an interest quorum are more likely to choose STEM careers. Using data from a national survey study of students‘ experiences in high school science, we compared the effect of five levels of peer interest reported in biology, chemistry, and physics courses on students‘ STEM career intentions. The results support our hypothesis, showing a strong, positive effect of an interest quorum even after controlling for differences between students that pose competing hypotheses such as previous STEM career interest, academic achievement, family support for mathematics and science, and gender. Smaller positive effects of interest quorums were observed for course performance in some cases, with no detrimental effects observed across the study. Last, significant effects persisted even after controlling for differences in teaching quality. This work emphasizes the likely importance of interest quorums for creating classroom environments that increase students’ intentions toward STEM careers while enhancing or maintaining course performance. PMID:28808678

  16. Interest in STEM is contagious for students in biology, chemistry, and physics classes.

    Science.gov (United States)

    Hazari, Zahra; Potvin, Geoff; Cribbs, Jennifer D; Godwin, Allison; Scott, Tyler D; Klotz, Leidy

    2017-08-01

    We report on a study of the effect of peers' interest in high school biology, chemistry, and physics classes on students' STEM (science, technology, engineering, and mathematics)-related career intentions and course achievement. We define an interest quorum as a science class where students perceive a high level of interest for the subject matter from their classmates. We hypothesized that students who experience such an interest quorum are more likely to choose STEM careers. Using data from a national survey study of students' experiences in high school science, we compared the effect of five levels of peer interest reported in biology, chemistry, and physics courses on students' STEM career intentions. The results support our hypothesis, showing a strong, positive effect of an interest quorum even after controlling for differences between students that pose competing hypotheses such as previous STEM career interest, academic achievement, family support for mathematics and science, and gender. Smaller positive effects of interest quorums were observed for course performance in some cases, with no detrimental effects observed across the study. Last, significant effects persisted even after controlling for differences in teaching quality. This work emphasizes the likely importance of interest quorums for creating classroom environments that increase students' intentions toward STEM careers while enhancing or maintaining course performance.

  17. Molecular Electron Density Theory: A Modern View of Reactivity in Organic Chemistry.

    Science.gov (United States)

    Domingo, Luis R

    2016-09-30

    A new theory for the study of the reactivity in Organic Chemistry, named Molecular Electron Density Theory (MEDT), is proposed herein. MEDT is based on the idea that while the electron density distribution at the ground state is responsible for physical and chemical molecular properties, as proposed by the Density Functional Theory (DFT), the capability for changes in electron density is responsible for molecular reactivity. Within MEDT, the reactivity in Organic Chemistry is studied through a rigorous quantum chemical analysis of the changes of the electron density as well as the energies associated with these changes along the reaction path in order to understand experimental outcomes. Studies performed using MEDT allow establishing a modern rationalisation and to gain insight into molecular mechanisms and reactivity in Organic Chemistry.

  18. A Research Module for the Organic Chemistry Laboratory: Multistep Synthesis of a Fluorous Dye Molecule.

    Science.gov (United States)

    Slade, Michael C; Raker, Jeffrey R; Kobilka, Brandon; Pohl, Nicola L B

    2014-01-14

    A multi-session research-like module has been developed for use in the undergraduate organic teaching laboratory curriculum. Students are tasked with planning and executing the synthesis of a novel fluorous dye molecule and using it to explore a fluorous affinity chromatography separation technique, which is the first implementation of this technique in a teaching laboratory. Key elements of the project include gradually introducing students to the use of the chemical literature to facilitate their searching, as well as deliberate constraints designed to force them to think critically about reaction design and optimization in organic chemistry. The project also introduces students to some advanced laboratory practices such as Schlenk techniques, degassing of reaction mixtures, affinity chromatography, and microwave-assisted chemistry. This provides students a teaching laboratory experience that closely mirrors authentic synthetic organic chemistry practice in laboratories throughout the world.

  19. New perspectives for organic chemistry and biochemistry in VUV: reaction kinetics, chirality and thermochemistry. Summaries

    International Nuclear Information System (INIS)

    Nahon, Laurent; Field, David; Gerber, Thomas; Knopp, Gregor; Beaud, Paul; Radi, Peter; Tulej, Marek; Dedonder-Lardeux, Claude; Jung, J.M.; Laprevote, Olivier; Thissen, Roland; Le Barbu, K.; Lahmani, F.; Zehnacker, A.; Maurizot, Jean Claude; Barbier, Bernard; Kagan, Henri B.

    2001-10-01

    The aim of this workshop was to examine the conditions of use of VUV for the study of complex molecular systems, and notably bio-molecules, a domain which is greatly expanding. The conclusions of this one-day workshop should allow to define new fields of utilization of the synchrotron radiation in VUV, to precise certain performances that are needed for the transferred line, to establish the complementarities with other VUV sources (lasers, free electron lasers, lamps) and to determine the eventual need for a second low energy light line at SOLEIL. The titles of the various abstract papers presented are (two papers are in English, the rest is in French): SU5, a high resolution and variable polarization VUV line that should be transferred at SOLEIL; Interstellar organic chemistry (in English); Application of spectroscopic techniques in the VUV to combustion relevant molecules (in English); Gaseous phase reaction kinetics (bi-molecular reactions in collision and in aggregates); Liquids of biological interest (excitation and relaxation close to the ionization threshold); Successes and impediments in protein mass spectrometry (the potential contribution of VUV synchrotron radiation); Stereo-specific effects; Complexes between chiral molecules; circular dichroism of biomolecules; Exobiology; asymmetric synthesis (principles and recent results)

  20. Using Structure-Based Organic Chemistry Online Tutorials with 2 Automated Correction for Student Practice and Review

    OpenAIRE

    O'Sullivan, Timothy; Hargaden, Grainne

    2014-01-01

    This article describes the development and implementation of an open-access organic chemistry question bank for online tutorials and assessments at University College Cork and Dublin Institute of Technology. SOCOT (structure-based organic chemistry online tutorials) may be used to supplement traditional small-group tutorials, thereby allowing students to develop essential problem-solving skills in organic chemistry. This online approach may be used for both formative and summative assessment....

  1. mu SR in Organic and Free Radical Chemistry

    CERN Multimedia

    2002-01-01

    Experiment SC82 was begun as a simple attempt to substitute positive muons into polymer molecules, and thereby to use the @mSR technique to study the mechanical relaxation of the different molecular groups. \\\\ \\\\ The experiment has since developed in several directions and has produced a wealth of information on the properties of muonic molecules, and adequately demonstrated the potential of @mSR as applied to molecular physics and chemistry. Physics aspects are now covered by a new experiment code SC95.\\\\ \\\\ The present experiment includes studies where the position occupied by the muon in the molecule (or crystal lattice) is readily established and the @mSR signal is exploited to reveal the intrinsic properties of the material. In this respect the @mSR techniques may be regarded simply as an experimental tool to probe the molecular behaviour of a chemical system. \\\\ \\\\ Two main classes of application include the measurement of isotope effects, where differences between muonic and corresponding photonic radi...

  2. Volatile organic compound ratios as probes of halogen atom chemistry in the Arctic

    Directory of Open Access Journals (Sweden)

    P. B. Shepson

    2008-03-01

    Full Text Available Volatile organic compound concentration ratios can be used as indicators of halogen chemistry that occurs during ozone depletion events in the Arctic during spring. Here we use a combination of modeling and measurements of [acetone]/[propanal] as an indicator of bromine chemistry, and [isobutane]/[n-butane] and [methyl ethyl ketone]/[n-butane] are used to study the extent of chlorine chemistry during four ozone depletion events during the Polar Sunrise Experiment of 1995. Using a 0-D photochemistry model in which the input of halogen atoms is controlled and varied, the approximate ratio of [Br]/[Cl] can be estimated for each ozone depletion event. It is concluded that there must be an additional source of propanal (likely from the snowpack to correctly simulate the VOC chemistry of the Arctic, and further evidence that the ratio of Br atoms to Cl atoms can vary greatly during ozone depletion events is presented.

  3. Organic synthesis

    International Nuclear Information System (INIS)

    Lallemand, J.Y.; Fetizon, M.

    1988-01-01

    The 1988 progress report of the Organic Synthesis Chemistry laboratory (Polytechnic School, France), is presented. The laboratory activities are centered on the chemistry of natural products, which have a biological activity and on the development of new reactions, useful in the organic synthesis. The research works involve the following domains: the natural products chemistry which are applied in pharmacology, the plants and insects chemistry, the organic synthesis, the radical chemistry new reactions and the bio-organic physicochemistry. The published papers, the congress communications and the thesis are listed [fr

  4. An Enzyme Kinetics Experiment for the Undergraduate Organic Chemistry Laboratory

    Science.gov (United States)

    Olsen, Robert J.; Olsen, Julie A.; Giles, Greta A.

    2010-01-01

    An experiment using [superscript 1]H NMR spectroscopy to observe the kinetics of the acylase 1-catalyzed hydrolysis of "N"-acetyl-DL-methionine has been developed for the organic laboratory. The L-enantiomer of the reactant is hydrolyzed completely in less than 2 h, and [superscript 1]H NMR spectroscopic data from a single sample can be worked up…

  5. Culturing Reality: How Organic Chemistry Graduate Students Develop into Practitioners

    Science.gov (United States)

    Bhattacharyya, Gautam; Bodner, George M.

    2014-01-01

    Although one of the presumed aims of graduate training programs is to help students develop into practitioners of their chosen fields, very little is known about how this transition occurs. In the course of studying how graduate students learn to solve organic synthesis problems, we were able to identify some of the key factors in the epistemic…

  6. Geochemistry and Organic Chemistry on the Surface of Titan

    Science.gov (United States)

    Lunine, J. I.; Beauchamp, P.; Beauchamp, J.; Dougherty, D.; Welch, C.; Raulin, F.; Shapiro, R.; Smith, M.

    2001-01-01

    Titan's atmosphere produces a wealth of organic products from methane and nitrogen. These products, deposited on the surface in liquid and solid form, may interact with surface ices and energy sources to produce compounds of exobiological interest. Additional information is contained in the original extended abstract.

  7. Developing and Evaluating an Eighth Grade Curriculum Unit That Links Foundational Chemistry to Biological Growth: Using Student Measures to Evaluate the Promise of the Intervention

    Science.gov (United States)

    Herrmann-Abell, Cari F.; Flanagan, Jean C.; Roseman, Jo Ellen

    2013-01-01

    Students often have trouble understanding key biology ideas, in part because they lack an understanding of foundational chemistry ideas. AAAS [American Association for the Advancement of Science] is collaborating with BSCS [Biological Sciences Curriculum Study] in the development of a curriculum unit that connects core chemistry and biology ideas…

  8. Investigating Membranes: Using Artificial Membranes to Convey Chemistry and Biology Concepts

    Science.gov (United States)

    Zrelak, Yoshi; McCallister, Gary

    2009-01-01

    While not organic in nature, quick-"growing" artificial membranes can be a profound visual aid when teaching students about cellular processes and the chemical nature of membranes. Students are often intrigued when they see biological and chemical concepts come to life before their eyes. In this article, the authors share their approach to growing…

  9. Do organic surface films on sea salt aerosols influence atmospheric chemistry? ─ a model study

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2007-11-01

    Full Text Available Organic material from the ocean's surface can be incorporated into sea salt aerosol particles often producing a surface film on the aerosol. Such an organic coating can reduce the mass transfer between the gas phase and the aerosol phase influencing sea salt chemistry in the marine atmosphere. To investigate these effects and their importance for the marine boundary layer (MBL we used the one-dimensional numerical model MISTRA. We considered the uncertainties regarding the magnitude of uptake reduction, the concentrations of organic compounds in sea salt aerosols and the oxidation rate of the organics to analyse the possible influence of organic surfactants on gas and liquid phase chemistry with a special focus on halogen chemistry. By assuming destruction rates for the organic coating based on laboratory measurements we get a rapid destruction of the organic monolayer within the first meters of the MBL. Larger organic initial concentrations lead to a longer lifetime of the coating but lead also to an unrealistically strong decrease of O3 concentrations as the organic film is destroyed by reaction with O3. The lifetime of the film is increased by assuming smaller reactive uptake coefficients for O3 or by assuming that a part of the organic surfactants react with OH. With regard to tropospheric chemistry we found that gas phase concentrations for chlorine and bromine species decreased due to the decreased mass transfer between gas phase and aerosol phase. Aqueous phase chlorine concentrations also decreased but aqueous phase bromine concentrations increased. Differences for gas phase concentrations are in general smaller than for liquid phase concentrations. The effect on gas phase NO2 or NO is very small (reduction less than 5% whereas liquid phase NO2 concentrations increased in some cases by nearly 100%. We list suggestions for further laboratory studies which are needed for improved model studies.

  10. Organic Chemistry: From the Interstellar Medium to the Solar System

    Science.gov (United States)

    Sandford, Scott; Witteborn, Fred C. (Technical Monitor)

    1997-01-01

    This talk will review the various types of organic materials observed in different environments in the interstellar medium, discuss the processes by which these materials may have formed and been modified, and present the evidence supporting the contention that at least a fraction of this material survived incorporation, substantially unaltered, into our Solar System during its formation. The nature of this organic material is of direct interest to issues associated with the origin of life, both because this material represents a large fraction of the Solar System inventory of the biogenically-important elements, and because many of the compounds in this inventory have biogenic implications. Several specific examples of such molecules will be briefly discussed.

  11. Flow Electrolysis Cells for the Synthetic Organic Chemistry Laboratory.

    Science.gov (United States)

    Pletcher, Derek; Green, Robert A; Brown, Richard C D

    2017-09-18

    Electrosynthesis has much to offer to the synthetic organic chemist. But in order to be widely accepted as a routine procedure in an organic synthesis laboratory, electrosynthesis needs to be presented in a much more user-friendly way. The literature is largely based on electrolysis in a glass beaker or H-cells that often give poor performance for synthesis with a very slow rate of conversion and, often, low selectivity and reproducibility. Flow cells can lead to much improved performance. Electrolysis is participating in the trend toward continuous flow synthesis, and this has led to a number of innovations in flow cell design that make possible selective syntheses with high conversion of reactant to product with a single passage of the reactant solution through the cell. In addition, the needs of the synthetic organic chemist can often be met by flow cells operating with recycle of the reactant solution. These cells give a high rate of product formation while the reactant concentration is high, but they perform best at low conversion. Both approaches are considered in this review and the important features of each cell design are discussed. Throughout, the application of the cell designs is illustrated with syntheses that have been reported.

  12. Correlation of Preadmission Organic Chemistry Courses and Academic Performance in Biochemistry at a Midwest Chiropractic Doctoral Program*

    Science.gov (United States)

    McRae, Marc P.

    2010-01-01

    Purpose: Organic chemistry has been shown to correlate with academic success in the preclinical years of medicine, dentistry, and graduate physiology. The purpose of this study is to examine the relationship between undergraduate organic chemistry grades and first-semester biochemistry grades at a Midwest chiropractic doctoral program. Methods: Students enrolled in a first-semester biochemistry course who had completed the prerequisite courses in organic chemistry offered at this same institution were entered into the study. The total grade for each of the three courses was calculated using the midterm and final exam raw scores with a weighting of 50% each. Analysis consisted of obtaining correlation coefficients between the total grades of organic 1 with biochemistry and organic 2 with biochemistry. Using the biochemistry total grade, the students were divided into quartiles and course grades for both organic chemistry 1 and 2 were calculated. Results: For the 109 students in the study, the correlation coefficient between the biochemistry and organic chemistry 1 and biochemistry and organic chemistry 2 courses was r = 0.744 and r = 0.725, respectively. The difference in organic chemistry grades between those in the first and fourth quartiles was 63.2% and 86.9% for organic chemistry 1 (p academic success in a chiropractic biochemistry course. Knowledge of such a relationship could prove useful to identify students who may potentially run into academic difficulty with first-year biochemistry PMID:20480012

  13. The role of energy in the emergence of biology from chemistry.

    Science.gov (United States)

    Dibrova, Daria V; Chudetsky, Michail Y; Galperin, Michael Y; Koonin, Eugene V; Mulkidjanian, Armen Y

    2012-10-01

    Any scenario of the transition from chemistry to biology should include an "energy module" because life can exist only when supported by energy flow(s). We addressed the problem of primordial energetics by combining physico-chemical considerations with phylogenomic analysis. We propose that the first replicators could use abiotically formed, exceptionally photostable activated cyclic nucleotides both as building blocks and as the main energy source. Nucleoside triphosphates could replace cyclic nucleotides as the principal energy-rich compounds at the stage of the first cells, presumably because the metal chelates of nucleoside triphosphates penetrated membranes much better than the respective metal complexes of nucleoside monophosphates. The ability to exploit natural energy flows for biogenic production of energy-rich molecules could evolve only gradually, after the emergence of sophisticated enzymes and ion-tight membranes. We argue that, in the course of evolution, sodium-dependent membrane energetics preceded the proton-based energetics which evolved independently in bacteria and archaea.

  14. 'Thunder' - Shock waves in pre-biological organic synthesis.

    Science.gov (United States)

    Bar-Nun, A.; Tauber, M. E.

    1972-01-01

    Theoretical study of the gasdynamics and chemistry of lightning-produced shock waves in a postulated primordial reducing atmosphere. It is shown that the conditions are similar to those encountered in a previously performed shock-tube experiment which resulted in 36% of the ammonia in the original mixture being converted into amino acids. The calculations give the (very large) energy rate of about 0.4 cal/sq cm/yr available for amino acid production, supporting previous hypotheses that 'thunder' could have been responsible for efficient large-scale production of organic molecules serving as precursors of life.

  15. Using Green Chemistry Principles as a Framework to Incorporate Research into the Organic Laboratory Curriculum

    Science.gov (United States)

    Lee, Nancy E.; Gurney, Rich; Soltzberg, Leonard

    2014-01-01

    Despite the accepted pedagogical value of integrating research into the laboratory curriculum, this approach has not been widely adopted. The activation barrier to this change is high, especially in organic chemistry, where a large number of students are required to take this course, special glassware or setups may be needed, and dangerous…

  16. Adapting to Student Learning Styles: Engaging Students with Cell Phone Technology in Organic Chemistry Instruction

    Science.gov (United States)

    Pursell, David P.

    2009-01-01

    Students of organic chemistry traditionally make 3 x 5 in. flash cards to assist learning nomenclature, structures, and reactions. Advances in educational technology have enabled flash cards to be viewed on computers, offering an endless array of drilling and feedback for students. The current generation of students is less inclined to use…

  17. A Learning-Cycle-Based Organic Chemistry Laboratory Program for Students in Dietetics.

    Science.gov (United States)

    Mueller, William J.

    1982-01-01

    The laboratory of an organic chemistry course for dietetics students is based on the learning cycle approach (exploration, invention-concept introduction, and concept application). The laboratory program is divided into four sections: lab techniques, compound types, reaction types, and reaction characteristics. (SK)

  18. Computer-Assisted Instruction in Undergraduate Organic Chemistry: Design, Application, and Evaluation. Technical Report 10.

    Science.gov (United States)

    Culp, George

    The computer-assisted instruction (CAI) program in undergraduate organic chemistry at the University of Texas was evaluated by an experimental design in 1969 and found to be successful. This report discusses in detail the formation of the design, its application, and the method of evaluation. The program itself included 15 teaching modules that…

  19. Minimal Impact of Organic Chemistry Prerequisite on Student Performance in Introductory Biochemistry

    Science.gov (United States)

    Wright, Robin; Cotner, Sehoya; Winkel, Amy

    2009-01-01

    Curriculum design assumes that successful completion of prerequisite courses will have a positive impact on student performance in courses that require the prerequisite. We recently had the opportunity to test this assumption concerning the relationship between completion of the organic chemistry prerequisite and performance in introductory…

  20. The Role of Spatial Ability and Strategy Preference for Spatial Problem Solving in Organic Chemistry

    Science.gov (United States)

    Stieff, Mike; Ryu, Minjung; Dixon, Bonnie; Hegarty, Mary

    2012-01-01

    In organic chemistry, spatial reasoning is critical for reasoning about spatial relationships in three dimensions and representing spatial information in diagrams. Despite its importance, little is known about the underlying cognitive components of spatial reasoning and the strategies that students employ to solve spatial problems in organic…

  1. 2005 Nobel Prize in Chemistry: Development of the Olefin Metathesis Method in Organic Synthesis

    Science.gov (United States)

    Casey, Charles P.

    2006-01-01

    The 2005 Nobel Prize in Chemistry was awarded "for the development of the metathesis method in organic synthesis". The discoveries of the laureates provided a chemical reaction used daily in the chemical industry for the efficient and more environmentally friendly production of important pharmaceuticals, fuels, synthetic fibers, and many other…

  2. A Survey of the Practices, Procedures, and Techniques in Undergraduate Organic Chemistry Teaching Laboratories

    Science.gov (United States)

    Martin, Christopher B.; Schmidt, Monica; Soniat, Michael

    2011-01-01

    A survey was conducted of four-year institutions that teach undergraduate organic chemistry laboratories in the United States. The data include results from over 130 schools, describes the current practices at these institutions, and discusses the statistical results such as the scale of the laboratories performed, the chemical techniques applied,…

  3. Engaging Organic Chemistry Students Using ChemDraw for iPad

    Science.gov (United States)

    Morsch, Layne A.; Lewis, Michael

    2015-01-01

    Drawing structures, mechanisms, and syntheses is a vital part of success in organic chemistry courses. ChemDraw for iPad has been used to increase classroom experiences in the preparation of high quality chemical drawings. The embedded Flick-to-Share allows for simple, real-time exchange of ChemDraw documents. ChemDraw for iPad also allows…

  4. The Relationship of Test Performance to ISDP Rating in Organic Chemistry Texts.

    Science.gov (United States)

    Choi, Soo-Young; And Others

    1979-01-01

    Describes the Instructional Strategy Diagnostic Profile (ISDP)--an analytic tool that facilitates the evaluation and revision of existing instruction and the design of new instruction--and recounts its use in comparing two textbooks to determine the most appropriate for an organic chemistry course. (JEG)

  5. Development and Use of Online Prelaboratory Activities in Organic Chemistry to Improve Students' Laboratory Experience

    Science.gov (United States)

    Chaytor, Jennifer L.; Al Mughalaq, Mohammad; Butler, Hailee

    2017-01-01

    Online prelaboratory videos and quizzes were prepared for all experiments in CHEM 231, Organic Chemistry I Laboratory. It was anticipated that watching the videos would help students be better prepared for the laboratory, decrease their anxiety surrounding the laboratory, and increase their understanding of the theories and concepts presented.…

  6. A New Higher Education Curriculum in Organic Chemistry: What Questions Should Be Asked?

    Science.gov (United States)

    Lafarge, David L.; Morge, Ludovic M.; Méheut, Martine M.

    2014-01-01

    Organic chemistry is often considered to be a difficult subject to teach and to learn, particularly as students prefer to resort to memorization alone rather than reasoning using models from chemical reactivity. Existing studies have led us to suggest principles for redefining the curriculum, ranging from its overall structure to the tasks given…

  7. A Performance Enhanced Interactive Learning Workshop Model as a Supplement for Organic Chemistry Instruction

    Science.gov (United States)

    Phillips, Karen E. S.; Grose-Fifer, Jilliam

    2011-01-01

    In this study, the authors describe a Performance Enhanced Interactive Learning (PEIL) workshop model as a supplement for organic chemistry instruction. This workshop model differs from many others in that it includes public presentations by students and other whole-class-discussion components that have not been thoroughly investigated in the…

  8. Formalizing the First Day in an Organic Chemistry Laboratory Using a Studio-Based Approach

    Science.gov (United States)

    Collison, Christina G.; Cody, Jeremy; Smith, Darren; Swartzenberg, Jennifer

    2015-01-01

    A novel studio-based lab module that incorporates student-centered activities was designed and implemented to introduce second-year undergraduate students to the first-semester organic chemistry laboratory. The "First Day" studio module incorporates learning objectives for the course, lab safety, and keeping a professional lab notebook.

  9. Gender Fair Efficacy of Concept Mapping Tests in Identifying Students' Difficulties in High School Organic Chemistry

    Science.gov (United States)

    Gafoor, Kunnathodi Abdul; Shilna, V.

    2014-01-01

    In view of the perceived difficulty of organic chemistry unit for high schools students, this study examined the usefulness of concept mapping as a testing device to assess students' difficulty in the select areas. Since many tests used for identifying students misconceptions and difficulties in school subjects are observed to favour one or the…

  10. Students' Perceptions of a Project-Based Organic Chemistry Laboratory Environment: A Phenomenographic Approach

    Science.gov (United States)

    Burrows, Nikita L.; Nowak, Montana K.; Mooring, Suazette R.

    2017-01-01

    Students can perceive the laboratory environment in a variety of ways that can affect what they take away from the laboratory course. This qualitative study characterizes undergraduate students' perspectives of a project-based Organic Chemistry laboratory using the theoretical framework of phenomenography. Eighteen participants were interviewed in…

  11. Students' Interpretations of Mechanistic Language in Organic Chemistry before Learning Reactions

    Science.gov (United States)

    Galloway, Kelli R.; Stoyanovich, Carlee; Flynn, Alison B.

    2017-01-01

    Research on mechanistic thinking in organic chemistry has shown that students attribute little meaning to the electron-pushing (i.e., curved arrow) formalism. At the University of Ottawa, a new curriculum has been developed in which students are taught the electron-pushing formalism prior to instruction on specific reactions--this formalism is…

  12. Using Web-Based Video as an Assessment Tool for Student Performance in Organic Chemistry

    Science.gov (United States)

    Tierney, John; Bodek, Matthew; Fredricks, Susan; Dudkin, Elizabeth; Kistler, Kurt

    2014-01-01

    This article shows the potential for using video responses to specific questions as part of the assessment process in an organic chemistry class. These exercises have been used with a postbaccalaureate cohort of 40 students, learning in an online environment, over a period of four years. A second cohort of 25 second-year students taking the…

  13. The Flipped Classroom for Teaching Organic Chemistry in Small Classes: Is It Effective?

    Science.gov (United States)

    Fautch, Jessica M.

    2015-01-01

    The flipped classroom is a pedagogical approach that moves course content from the classroom to homework, and uses class time for engaging activities and instructor-guided problem solving. The course content in a sophomore level Organic Chemistry I course was assigned as homework using video lectures, followed by a short online quiz. In class,…

  14. A Historical Analysis of the Curriculum of Organic Chemistry Using ACS Exams as Artifacts

    Science.gov (United States)

    Raker, Jeffrey R.; Holme, Thomas A.

    2013-01-01

    Standardized examinations, such as those developed and disseminated by the ACS Examinations Institute, are artifacts of the teaching of a course and over time may provide a historical perspective on how curricula have changed and evolved. This study investigated changes in organic chemistry curricula across a 60-year period by evaluating 18 ACS…

  15. Effectiveness of E-Content Package on Teaching IUPAC Nomenclature of Organic Chemistry at Undergraduate Level

    Science.gov (United States)

    Devendiran, G.; Vakkil, M.

    2017-01-01

    This study attempts to discover the effectiveness of an e-content package when teaching IUPAC nomenclature of organic chemistry at the undergraduate level. The study consisted of a Pre-test-Post-test Non Equivalent Groups Design, and the sample of 71 (n = 71) students were drawn from two colleges. The overall study was divided into two groups, an…

  16. Independent Synthesis Projects in the Organic Chemistry Teaching Laboratories: Bridging the Gap between Student and Researcher

    Science.gov (United States)

    Keller, Valerie A.; Kendall, Beatrice Lin

    2017-01-01

    Science educators strive to teach students how to be well-rounded scientists with the ability to problem solve, anticipate errors, and adapt to unexpected roadblocks. Traditional organic chemistry experiments seldom teach these skills, no matter how novel or contemporary the subject material. This paper reports on the success of a quarter-long…

  17. A Guided Inquiry Liquid/Liquid Extractions Laboratory for Introductory Organic Chemistry

    Science.gov (United States)

    Raydo, Margaret L.; Church, Megan S.; Taylor, Zane W.; Taylor, Christopher E.; Danowitz, Amy M.

    2015-01-01

    A guided inquiry laboratory experiment for teaching liquid/liquid extractions to first semester undergraduate organic chemistry students is described. This laboratory is particularly useful for introductory students as the analytes that are separated are highly colored dye molecules. This allows students to track into which phase each analyte…

  18. Grade/Study-Performance Contracts, Enhanced Communication, Cooperative Learning, and Student Performance in Undergraduate Organic Chemistry.

    Science.gov (United States)

    Dougherty, Ralph C.

    1997-01-01

    Describes and evaluates a teaching strategy, designed to increase student retention while maintaining academic performance levels in undergraduate organic chemistry, that uses grade/study-performance contracts, enhanced communication using electronic mail, and cooperative learning. Concludes that a series of interventions can substantially…

  19. Visualizing Molecular Chirality in the Organic Chemistry Laboratory Using Cholesteric Liquid Crystals

    Science.gov (United States)

    Popova, Maia; Bretz, Stacey Lowery; Hartley, C. Scott

    2016-01-01

    Although stereochemistry is an important topic in second-year undergraduate organic chemistry, there are limited options for laboratory activities that allow direct visualization of macroscopic chiral phenomena. A novel, guided-inquiry experiment was developed that allows students to explore chirality in the context of cholesteric liquid crystals.…

  20. Green Oxidation of Menthol Enantiomers and Analysis by Circular Dichroism Spectroscopy: An Advanced Organic Chemistry Laboratory

    Science.gov (United States)

    Geiger, H. Cristina; Donohoe, James S.

    2012-01-01

    Green chemistry addresses environmental concerns associated with chemical processes and increases awareness of possible harmful effects of chemical reagents. Efficient reactions that eliminate or reduce the use of organic solvents or toxic reagents are increasingly available. A two-week experiment is reported that entails the calcium hypochlorite…

  1. Solvent-Free Wittig Reaction: A Green Organic Chemistry Laboratory Experiment

    Science.gov (United States)

    Leung, Sam H.; Angel, Stephen A.

    2004-01-01

    Some Wittig reactions can be carried out by grinding the reactants in a mortar with a pestle for about 20 minutes, as per investigation. A laboratory experiment involving a solvent-free Wittig reaction that can be completed in a three-hour sophomore organic chemistry laboratory class period, are developed.

  2. Structure Determination of Unknown Organic Liquids Using NMR and IR Spectroscopy: A General Chemistry Laboratory

    Science.gov (United States)

    Pavel, John T.; Hyde, Erin C.; Bruch, Martha D.

    2012-01-01

    This experiment introduced general chemistry students to the basic concepts of organic structures and to the power of spectroscopic methods for structure determination. Students employed a combination of IR and NMR spectroscopy to perform de novo structure determination of unknown alcohols, without being provided with a list of possible…

  3. Microwave-Assisted Chemistry: Synthetic Applications for Rapid Assembly of Nanomaterials and Organics

    Science.gov (United States)

    The magic of microwave (MW) heating technique, termed as the Bunsen burner of the 21th Century, has emerged as valuable alternative in synthesis of organics, polymers, inorganics, and nanomaterials. Important innovations in MW-assisted chemistry now enable chemists to prepare cat...

  4. Interdisciplinary Learning for Chemical Engineering Students from Organic Chemistry Synthesis Lab to Reactor Design to Separation

    Science.gov (United States)

    Armstrong, Matt; Comitz, Richard L.; Biaglow, Andrew; Lachance, Russ; Sloop, Joseph

    2008-01-01

    A novel approach to the Chemical Engineering curriculum sequence of courses at West Point enabled our students to experience a much more realistic design process, which more closely replicated a real world scenario. Students conduct the synthesis in the organic chemistry lab, then conduct computer modeling of the reaction with ChemCad and…

  5. Searching for Synthetic Antimicrobial Peptides: An Experiment for Organic Chemistry Students

    Science.gov (United States)

    Vasquez, Thomas E., Jr.; Saldan~a, Cristina; Muzikar, Katy A.; Mashek, Debra; Liu, Jane M.

    2016-01-01

    This laboratory experiment provides undergraduate students enrolled in organic chemistry the opportunity to design and synthesize their own peptide, which is then tested for antimicrobial activity. After reading a primary scientific paper on antimicrobial peptides, students design and synthesize their own hexapeptide that they hypothesize will…

  6. Fascinating chemistry or frustrating unpredictability : Observations in crystal engineering of metal–organic frameworks

    NARCIS (Netherlands)

    Goesten, M.G.; Kapteijn, F.; Gascon, J.

    2013-01-01

    Reticular design is a highly attractive concept, but coordination chemistry around the tectonic units of metal– organic frameworks (MOFs) and additional interplay with anionic and solvent species provide for dazzling complexity that effectively rules out structure prediction. We can however study

  7. Transforming the Organic Chemistry Lab Experience: Design, Implementation, and Evaluation of Reformed Experimental Activities--REActivities

    Science.gov (United States)

    Collison, Christina G.; Kim, Thomas; Cody, Jeremy; Anderson, Jason; Edelbach, Brian; Marmor, William; Kipsang, Rodgers; Ayotte, Charles; Saviola, Daniel; Niziol, Justin

    2018-01-01

    Reformed experimental activities (REActivities) are an innovative approach to the delivery of the traditional material in an undergraduate organic chemistry laboratory. A description of the design and implementation of REActivities at both a four- and two-year institution is discussed. The results obtained using a reformed teaching observational…

  8. Student Perceptions of Online Homework Use for Formative Assessment of Learning in Organic Chemistry.

    Science.gov (United States)

    Richards-Babb, Michelle; Curtis, Reagan; Georgieva, Zomitsa; Penn, John H

    2015-11-10

    Use of online homework as a formative assessment tool for organic chemistry coursework was examined. Student perceptions of online homework in terms of (i) its ranking relative to other course aspects, (ii) their learning of organic chemistry, and (iii) whether it improved their study habits and how students used it as a learning tool were investigated. Our students perceived the online homework as one of the more useful course aspects for learning organic chemistry content. We found a moderate and statistically significant correlation between online homework performance and final grade. Gender as a variable was ruled out since significant gender differences in overall attitude toward online homework use and course success rates were not found. Our students expressed relatively positive attitudes toward use of online homework with a majority indicating improved study habits (e.g., study in a more consistent manner). Our students used a variety of resources to remediate incorrect responses (e.g., class materials, general online materials, and help from others). However, 39% of our students admitted to guessing at times, instead of working to remediate incorrect responses. In large enrollment organic chemistry courses, online homework may act to bridge the student-instructor gap by providing students with a supportive mechanism for regulated learning of content.

  9. Using the Cambridge Structural Database to Teach Molecular Geometry Concepts in Organic Chemistry

    Science.gov (United States)

    Wackerly, Jay Wm.; Janowicz, Philip A.; Ritchey, Joshua A.; Caruso, Mary M.; Elliott, Erin L.; Moore, Jeffrey S.

    2009-01-01

    This article reports a set of two homework assignments that can be used in a second-year undergraduate organic chemistry class. These assignments were designed to help reinforce concepts of molecular geometry and to give students the opportunity to use a technological database and data mining to analyze experimentally determined chemical…

  10. Organic chemistry of Murchison meteorite: Carbon isotopic fractionation

    Science.gov (United States)

    Yuen, G. U.; Blair, N. E.; Desmarais, D. J.; Cronin, J. R.; Chang, S.

    1986-01-01

    The carbon isotopic composition of individual organic compounds of meteoritic origin remains unknown, as most reported carbon isotopic ratios are for bulk carbon or solvent extractable fractions. The researchers managed to determine the carbon isotopic ratios for individual hydrocarbons and monocarboxylic acids isolated from a Murchison sample by a freeze-thaw-ultrasonication technique. The abundances of monocarboxylic acids and saturated hydrocarbons decreased with increasing carbon number and the acids are more abundant than the hydrocarbon with the same carbon number. For both classes of compounds, the C-13 to C-12 ratios decreased with increasing carbon number in a roughly parallel manner, and each carboxylic acid exhibits a higher isotopic number than the hydrocarbon containing the same number of carbon atoms. These trends are consistent with a kinetically controlled synthesis of higher homologues for lower ones.

  11. Tholins - Organic chemistry of interstellar grains and gas

    Science.gov (United States)

    Sagan, C.; Khare, B. N.

    1979-01-01

    The paper discusses tholins, defined as complex organic solids formed by the interaction of energy - for example, UV light or spark discharge - with various mixtures of cosmically abundant gases - CH4, C2H6, NH3, H2O, HCHO, and H2S. It is suggested that tholins occur in the interstellar medium and are responsible for some of the properties of the interstellar grains and gas. Additional occurrences of tholins are considered. Tholins have been produced experimentally; 50 or so pyrolytic fragments of the brown, sometimes sticky substances have been identified by gas chromatography-mass spectrometry, and the incidence of these fragments in tholins produced by different procedures is reported.

  12. Microwave Assisted Organic Synthesis of Heterocycles in Aqueous Media: Recent Advances in Medicinal Chemistry.

    Science.gov (United States)

    Frecentese, Francesco; Saccone, Irene; Caliendo, Giuseppe; Corvino, Angela; Fiorino, Ferdinando; Magli, Elisa; Perissutti, Elisa; Severino, Beatrice; Santagada, Vincenzo

    2016-01-01

    Green chemistry is a discipline of great interest in medicinal chemistry. It involves all fields of chemistry and it is based on the principle to conduct chemical reactions protecting the environment at the same time, through the use of chemical procedures able to avoid pollution. In this context, water as solvent is a good choice because it is abundant, nontoxic, non-caustic, and non-combustible. Even if microwave assisted organic reactions in conventional solvents have quickly progressed, in the recent years medicinal chemists have focused their attention to processes deemed not dangerous for the environment, using nanotechnology and greener solvents as water. Several reports of reaction optimizations and selectivities, demonstrating the capability of microwave to allow the obtaining of increased yields have been recently published using water as solvent. In this review, we selected the available knowledge related to microwave assisted organic synthesis in aqueous medium, furnishing examples of the newest strategies to obtain useful scaffolds and novel derivatives for medicinal chemistry purposes. The intention of this review is to demonstrate the exclusive ability of MAOS in water as solvent or as co-solvent. For this purpose we report here the most representative applications of MAOS using water as solvent, focusing on medicinal chemistry processes leading to interesting nitrogen containing heterocycles with potential pharmaceutical applications.

  13. Apoc Social: A Mobile Interactive and Social Learning Platform for Collaborative Solving of Advanced Problems in Organic Chemistry.

    Science.gov (United States)

    Sievertsen, Niels; Carreira, Erick M

    2018-02-01

    Mobile devices such as smartphones are carried in the pockets of university students around the globe and are increasingly cheap to come by. These portable devices have evolved into powerful and interconnected handheld computers, which, among other applications, can be used as advanced learning tools and providers of targeted, curated content. Herein, we describe Apoc Social (Advanced Problems in Organic Chemistry Social), a mobile application that assists both learning and teaching college-level organic chemistry both in the classroom and on the go. With more than 750 chemistry exercises available, Apoc Social facilitates collaborative learning through discussion boards and fosters enthusiasm for complex organic chemistry.

  14. Quantum Mechanical Calculations in Collaborations with Experimental Chemistry: The Theoretical Organic Chemistry Perspective

    Science.gov (United States)

    Nguyen, Quynh Nhu Ngoc

    The results of quantum chemical calculations reveal that polyanionic gallium-based cages accelerate cyclization reactions of pentadienyl alcohols by significantly increasing basicity of the substrate hydroxyl group. The energy barrier for cyclization of the pentadienyl cation after water loss is already low in the background reaction and is altered fairly little by the cage. The calculations for other non-alcohol substrates also suggest that the cage increases the basicity of amine and phosphine groups, though to a lesser extend comparing to the alcohol substrate. Due to their twisting patterns, alpha-helical peptides are known to have overall "macrodipoles" along the principal axes as the result of the backbone carbonyl groups pointing toward the C-terminus. As the dipoles have implications in helical bundles, interactions with lipid bilayers, and distribution of charge, chemists have long been interested in employing the macrodipole in modifications of peptides' catalytic activities. In this studied, we examined the impact of both global and local noncovalent interactions between peptide catalysts and substrates in the first transesterification step, in hope of designing a better peptide catalysts to aid in ester metabolism. Quantum mechanical calculations helped predict whether the targeted medium-sized cyclic peptide products would more likely be the major products, before the experimental team invested extensive resources and time to carry out the syntheses. Many systems were found to favor the medium-sized cyclic peptides, whereas one system was predicted to result in polycyclic product, and the latter experimental observations agreed with these predictions. Naturally occurring cyclic peptides display various biological activities due to their diverse structures. Understanding the dominant structures of these peptides could help give insight into protein-protein interactions or substrate-protein binding. With the experimental NMR data obtained for the

  15. Biology, genome organization and evolution of parvoviruses in marine shrimp

    Science.gov (United States)

    A number of parvoviruses are now know to infect marine shrimp, and these viruses alone or in combination with other viruses have the potential to cause major losses in shrimp aquaculture globally. This review provides a comprehensive overview of the biology, genome organization, gene expression, and...

  16. Organic compounds in fluid inclusions of Archean quartz—Analogues of prebiotic chemistry on early Earth

    Science.gov (United States)

    Schreiber, Ulrich; Mayer, Christian; Schmitz, Oliver J.; Rosendahl, Pia; Bronja, Amela; Greule, Markus; Keppler, Frank; Mulder, Ines; Sattler, Tobias; Schöler, Heinz F.

    2017-01-01

    The origin of life is still an unsolved mystery in science. Hypothetically, prebiotic chemistry and the formation of protocells may have evolved in the hydrothermal environment of tectonic fault zones in the upper continental crust, an environment where sensitive molecules are protected against degradation induced e.g. by UV radiation. The composition of fluid inclusions in minerals such as quartz crystals which have grown in this environment during the Archean period might provide important information about the first organic molecules formed by hydrothermal synthesis. Here we present evidence for organic compounds which were preserved in fluid inclusions of Archean quartz minerals from Western Australia. We found a variety of organic compounds such as alkanes, halocarbons, alcohols and aldehydes which unambiguously show that simple and even more complex prebiotic organic molecules have been formed by hydrothermal processes. Stable-isotope analysis confirms that the methane found in the inclusions has most likely been formed from abiotic sources by hydrothermal chemistry. Obviously, the liquid phase in the continental Archean crust provided an interesting choice of functional organic molecules. We conclude that organic substances such as these could have made an important contribution to prebiotic chemistry which might eventually have led to the formation of living cells. PMID:28614348

  17. Organic compounds in fluid inclusions of Archean quartz-Analogues of prebiotic chemistry on early Earth.

    Science.gov (United States)

    Schreiber, Ulrich; Mayer, Christian; Schmitz, Oliver J; Rosendahl, Pia; Bronja, Amela; Greule, Markus; Keppler, Frank; Mulder, Ines; Sattler, Tobias; Schöler, Heinz F

    2017-01-01

    The origin of life is still an unsolved mystery in science. Hypothetically, prebiotic chemistry and the formation of protocells may have evolved in the hydrothermal environment of tectonic fault zones in the upper continental crust, an environment where sensitive molecules are protected against degradation induced e.g. by UV radiation. The composition of fluid inclusions in minerals such as quartz crystals which have grown in this environment during the Archean period might provide important information about the first organic molecules formed by hydrothermal synthesis. Here we present evidence for organic compounds which were preserved in fluid inclusions of Archean quartz minerals from Western Australia. We found a variety of organic compounds such as alkanes, halocarbons, alcohols and aldehydes which unambiguously show that simple and even more complex prebiotic organic molecules have been formed by hydrothermal processes. Stable-isotope analysis confirms that the methane found in the inclusions has most likely been formed from abiotic sources by hydrothermal chemistry. Obviously, the liquid phase in the continental Archean crust provided an interesting choice of functional organic molecules. We conclude that organic substances such as these could have made an important contribution to prebiotic chemistry which might eventually have led to the formation of living cells.

  18. Spicing Things up by Adding Color and Relieving Pain: The Use of "Napoleon's Buttons" in Organic Chemistry

    Science.gov (United States)

    Bucholtz, Kevin M.

    2011-01-01

    For some students, organic chemistry can be a distant subject and unrelated to any courses they have seen in their college careers. To develop a more contextual learning experience in organic chemistry, an additional text, "Napoleon's Buttons: 17 Molecules That Changed History," by Penny Le Couteur and Jay Burreson, was incorporated as a…

  19. Using Commercially Available Techniques to Make Organic Chemistry Representations Tactile and More Accessible to Students with Blindness or Low Vision

    Science.gov (United States)

    Supalo, Cary A.; Kennedy, Sean H.

    2014-01-01

    Organic chemistry courses can present major obstacles to access for students with blindness or low vision (BLV). In recent years, efforts have been made to represent organic chemistry concepts in tactile forms for blind students. These methodologies are described in this manuscript. Further work being done at Illinois State University is also…

  20. Implementation of picoSpin Benchtop NMR Instruments into Organic Chemistry Teaching Laboratories through Spectral Analysis of Fischer Esterification Products

    Science.gov (United States)

    Yearty, Kasey L.; Sharp, Joseph T.; Meehan, Emma K.; Wallace, Doyle R.; Jackson, Douglas M.; Morrison, Richard W.

    2017-01-01

    [Superscript 1]H NMR analysis is an important analytical technique presented in introductory organic chemistry courses. NMR instrument access is limited for undergraduate organic chemistry students due to the size of the instrument, price of NMR solvents, and the maintenance level required for instrument upkeep. The University of Georgia Chemistry…

  1. Perry's Scheme of Intellectual and Epistemological Development as a Framework for Describing Student Difficulties in Learning Organic Chemistry

    Science.gov (United States)

    Grove, Nathaniel P.; Bretz, Stacey Lowery

    2010-01-01

    We have investigated student difficulties with the learning of organic chemistry. Using Perry's Model of Intellectual Development as a framework revealed that organic chemistry students who function as dualistic thinkers struggle with the complexity of the subject matter. Understanding substitution/elimination reactions and multi-step syntheses is…

  2. The use of domestic microwave oven in experimental classes of organic chemistry: salicylaldehyde nitration

    International Nuclear Information System (INIS)

    Teixeira, Eurides Francisco; Santos, Ana Paula Bernardo dos; Bastos, Renato Saldanha; Pinto, Angelo C.

    2010-01-01

    The use of microwave in chemistry has known benefits over conventional heating methods, e.g. reduced reaction times, chemical yield improvement and the possibility if reducing or eliminating the use of organic solvents. We describe herein a procedure for the nitration of salicylaldehyde in water using a domestic microwave oven, which can be used as an experiment in the undergraduate chemistry laboratory. The experiment involves safe and rapid preparation and identification of the position isomers by thin layer chromatography and 1 H NMR, or by their melting points. (author)

  3. Nobel Prize in Chemistry. Development of the Olefin Metathesis Method in Organic Synthesis

    Science.gov (United States)

    Casey, Charles P.

    2006-02-01

    The 2005 Nobel Prize in Chemistry was awarded to Yves Chauvin of the Institut Français du Pétrole, Robert H. Grubbs of CalTech, and Richard R. Schrock of MIT "for development of the metathesis method in organic synthesis". The discoveries of the laureates provided a chemical reaction now used daily in the chemical industry for the efficient and more environmentally friendly production of important pharmaceuticals, fuels, synthetic fibers, and many other products. This article tells the story of how olefin metathesis became a truly useful synthetic transformation and a triumph for mechanistic chemistry, and illustrates the importance of fundamental research. See JCE Featured Molecules .

  4. BIO-ORGANIC CHEMISTRY QUARTERLY REPORT - MARCH THROUGH MAY1961

    Energy Technology Data Exchange (ETDEWEB)

    Various

    1961-06-29

    The study of meteorite Murray has been reported in previous Quarterly Reports. This report gives further results with Murray, and information on another meteorite, Orgueil. A sample of Orgueil was sent from the Museum National d Histoire Naturelle, Paris. It fell in several pieces over an area of 2 square miles near Orgueil, France, in 1864. The elemental analysis of this meteorite is shown in Table 1. They extracted a 10.07-g sample of this meteorite with water, using the same procedure as that for Murray. The water extracted 1.32 g, which is at least twice as much material as was water-extracted from Murray. The elemental analysis of the water extract is given in Table II and its uv spectrum is shown in Figure 1. From an x-ray diffraction pattern it was determined that the water extract contained mostly MgSO{sub 4} {center_dot} 6H{sub 2}O with some calcium sulfate. Their spectrum (Figure 2) shows a strong SO{sub 4} band at 1100 cm{sup -1}, = strong H{sub 2}O bands at 1650 cm{sup -1} and 3200-3600 cm{sup -1}, and some unidentified peaks at 2300, 1400, and 980 cm{sup -1}. The approximately 8 g of Orgueil left after the water extraction was then extracted with purified chloroform. Approximately 50 mg of yellow material was extracted. Its uv spectrum is shown in Figure 3 and is identical to the spectrum of elemental sulfur. Whatever else may be extracted from the meteorites by organic solvents, the uv spectra show only sulfur.

  5. "Solvent-in-salt" systems for design of new materials in chemistry, biology and energy research.

    Science.gov (United States)

    Azov, Vladimir A; Egorova, Ksenia S; Seitkalieva, Marina M; Kashin, Alexey S; Ananikov, Valentine P

    2018-02-21

    Inorganic and organic "solvent-in-salt" (SIS) systems have been known for decades but have attracted significant attention only recently. Molten salt hydrates/solvates have been successfully employed as non-flammable, benign electrolytes in rechargeable lithium-ion batteries leading to a revolution in battery development and design. SIS with organic components (for example, ionic liquids containing small amounts of water) demonstrate remarkable thermal stability and tunability, and present a class of admittedly safer electrolytes, in comparison with traditional organic solvents. Water molecules tend to form nano- and microstructures (droplets and channel networks) in ionic media impacting their heterogeneity. Such microscale domains can be employed as microreactors for chemical and enzymatic synthesis. In this review, we address known SIS systems and discuss their composition, structure, properties and dynamics. Special attention is paid to the current and potential applications of inorganic and organic SIS systems in energy research, chemistry and biochemistry. A separate section of this review is dedicated to experimental methods of SIS investigation, which is crucial for the development of this field.

  6. Delayed Reaction: The Tardy Embrace of Physical Organic Chemistry by the German Chemical Community.

    Science.gov (United States)

    Weininger, Stephen J

    2018-02-01

    The emergence of physical organic chemistry, which focuses on the mechanisms and structures of organic reactions and molecules using the tools of physical chemistry, was a major development in twentieth-century chemistry. It first flourished in the interwar period, in the UK and then in the US. Germany, by contrast, did not embrace the field until almost a half century later. The great success of classical organic chemistry, especially in synthesis, encouraged indifference to the new field among German chemists, as did their inductivist research philosophy, as enunciated by Walter Hückel's ground-breaking textbook (1931). This author also resisted new concepts and representations, especially those of the American theoretician, Linus Pauling. The arrival of the Nazi regime reinforced such resistance. Postwar conditions initiated a reaction against this conservative, nationalistic attitude, especially in the American Occupation Zone. Exposure to American textbooks and visiting lecturers influenced attitudes of younger chemists. The accompanying shift towards a more explanatory, less hierarchical mode of pedagogy was consonant with larger social and political developments.

  7. Calamintha nepeta (L. Savi and its Main Essential Oil Constituent Pulegone: Biological Activities and Chemistry

    Directory of Open Access Journals (Sweden)

    Mijat Božović

    2017-02-01

    Full Text Available Medicinal plants play an important role in the treatment of a wide range of diseases, even if their chemical constituents are not always completely recognized. Observations on their use and efficacy significantly contribute to the disclosure of their therapeutic properties. Calamintha nepeta (L. Savi is an aromatic herb with a mint-oregano flavor, used in the Mediterranean areas as a traditional medicine. It has an extensive range of biological activities, including antimicrobial, antioxidant and anti-inflammatory, as well as anti-ulcer and insecticidal properties. This study aims to review the scientific findings and research reported to date on Calamintha nepeta (L. Savi that prove many of the remarkable various biological actions, effects and some uses of this species as a source of bioactive natural compounds. On the other hand, pulegone, the major chemical constituent of Calamintha nepeta (L. Savi essential oil, has been reported to exhibit numerous bioactivities in cells and animals. Thus, this integrated overview also surveys and interprets the present knowledge of chemistry and analysis of this oxygenated monoterpene, as well as its beneficial bioactivities. Areas for future research are suggested

  8. Mentha suaveolens Ehrh. (Lamiaceae) Essential Oil and Its Main Constituent Piperitenone Oxide: Biological Activities and Chemistry.

    Science.gov (United States)

    Božović, Mijat; Pirolli, Adele; Ragno, Rino

    2015-05-13

    Since herbal medicines play an important role in the treatment of a wide range of diseases, there is a growing need for their quality control and standardization. Mentha suaveolens Ehrh. (MS) is an aromatic herb with fruit and a spearmint flavor, used in the Mediterranean areas as a traditional medicine. It has an extensive range of biological activities, including cytotoxic, antimicrobial, antioxidant, anti-inflammatory, hypotensive and insecticidal properties, among others. This study aims to review the scientific findings and research reported to date on MS that prove many of the remarkable various biological actions, effects and some uses of this species as a source of bioactive natural compounds. On the other hand, piperitenone oxide (PO), the major chemical constituent of the carvone pathway MS essential oil, has been reported to exhibit numerous bioactivities in cells and animals. Thus, this integrated overview also surveys and interprets the present knowledge of chemistry and analysis of this oxygenated monoterpene, as well as its beneficial bioactivities. Areas for future research are suggested.

  9. Processes that Drove the Transition from Chemistry to Biology: Concepts and Evidence

    Science.gov (United States)

    Pohorille, Andrew

    2012-01-01

    Two properties are particularly germane to the transition from chemistry to biology. One is the emergence of complex molecules (polymers) capable of performing non-trivial functions, such as catalysis, energy transduction or transport across cell walls. The other is the ability of several functions to work in concert to provide reproductive advantage to systems hosting these functions. Biological systems exhibit these properties at remarkable levels of efficiency and accuracy in a way that appears effortless. However, dissection of these properties reveals great complexities that are involved. This opens a question: how a simple, ancestral system could have acquired the required properties? Other questions follow. What are the chances that a functional polymer emerges at random? What is the minimum structural complexity of a polymer to carry out a function at a reasonable level of efficiency? Can we identify concrete, protobiologically plausible mechanisms that yield advantageous coupling between different functions? These and similar questions are at the core of the main topic of this session: how soulless chemistry became life? Clearly, we do not have complete answers to any of these questions. However, in recent years a number of new and sometimes unexpected clues have been brought to light. Of particular interest are proteins because they are the main functional polymers in contemporary cells. The emergence of protein functions is a puzzle. It is widely accepted that a well ]defined, compact structure (fold) is a prerequisite for function. It is equally widely accepted that compact folds are rare among random amino acid polymers. Then, how did protein functionality start? According to one hypothesis well folded were preceded by their poorly folded, yet still functional ancestors. Only recently, however, experimental evidence supporting this hypothesis has been presented. In particular, a small enzyme capable of ligating two RNA fragments with the rate of 106

  10. 25th anniversary article: progress in chemistry and applications of functional indigos for organic electronics.

    Science.gov (United States)

    Głowacki, Eric Daniel; Voss, Gundula; Sariciftci, Niyazi Serdar

    2013-12-17

    Indigo and its derivatives are dyes and pigments with a long and distinguished history in organic chemistry. Recently, applications of this 'old' structure as a functional organic building block for organic electronics applications have renewed interest in these molecules and their remarkable chemical and physical properties. Natural-origin indigos have been processed in fully bio-compatible field effect transistors, operating with ambipolar mobilities up to 0.5 cm(2) /Vs and air-stability. The synthetic derivative isoindigo has emerged as one of the most successful building-blocks for semiconducting polymers for plastic solar cells with efficiencies > 5%. Another isomer of indigo, epindolidione, has also been shown to be one of the best reported organic transistor materials in terms of mobility (∼2 cm(2) /Vs) and stability. This progress report aims to review very recent applications of indigoids in organic electronics, but especially to logically bridge together the hereto independent research directions on indigo, isoindigo, and other materials inspired by historical dye chemistry: a field which was the root of the development of modern chemistry in the first place. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Aqueous chemistry and its role in secondary organic aerosol (SOA formation

    Directory of Open Access Journals (Sweden)

    Y. B. Lim

    2010-11-01

    Full Text Available There is a growing understanding that secondary organic aerosol (SOA can form through reactions in atmospheric waters (i.e., clouds, fogs, and aerosol water. In clouds and wet aerosols, water-soluble organic products of gas-phase photochemistry dissolve into the aqueous phase where they can react further (e.g., with OH radicals to form low volatility products that are largely retained in the particle phase. Organic acids, oligomers and other products form via radical and non-radical reactions, including hemiacetal formation during droplet evaporation, acid/base catalysis, and reaction of organics with other constituents (e.g., NH4+.

    This paper provides an overview of SOA formation through aqueous chemistry, including atmospheric evidence for this process and a review of radical and non-radical chemistry, using glyoxal as a model precursor. Previously unreported analyses and new kinetic modeling are reported herein to support the discussion of radical chemistry. Results suggest that reactions with OH radicals tend to be faster and form more SOA than non-radical reactions. In clouds these reactions yield organic acids, whereas in wet aerosols they yield large multifunctional humic-like substances formed via radical-radical reactions and their O/C ratios are near 1.

  12. Current Status and Future Perspectives in Flavor Research: Highlights of the 11th Wartburg Symposium on Flavor Chemistry & Biology.

    Science.gov (United States)

    Hofmann, Thomas; Krautwurst, Dietmar; Schieberle, Peter

    2018-03-14

    The 11th Wartburg Symposium on Flavor Chemistry & Biology, held at the hotel "Auf der Wartburg" in Eisenach, Germany, from June 21 to 24 in 2016, offered a venue for global exchange on cutting-edge research in chemistry and biology of odor and taste. The focus areas were (1) functional flavor genomics and biotechnology, (2) flavor generation and precursors, (3) new approaches and precursors, (4) new approaches and technologies, (5) new molecules and structure/activity relationships, (6) food-borne bioactives and chemosensory health prevention, and (7) chemosensory reception, processing, and perception. Selected from more than 250 applicants, 160 distinguished scientists and rising stars from academia and industry from 24 countries participated in this multidisciplinary event. This special issue comprises a selection of 33 papers from oral presentations and poster contributions and is prefaced by this symposium introduction to carve out essential achievements in odor and taste chemistry and to share future research perspectives.

  13. Separating the effects of organic matter-mineral interactions and organic matter chemistry on the sorption of diuron and phenanthrene.

    Science.gov (United States)

    Ahangar, Ahmad Gholamalizadeh; Smernik, Ronald J; Kookana, Rai S; Chittleborough, David J

    2008-06-01

    Even though it is well established that soil C content is the primary determinant of the sorption affinity of soils for non-ionic compounds, it is also clear that organic carbon-normalized sorption coefficients (K(OC)) vary considerably between soils. Two factors that may contribute to K(OC) variability are variations in organic matter chemistry between soils and interactions between organic matter and soil minerals. Here, we quantify these effects for two non-ionic sorbates-diuron and phenanthrene. The effect of organic matter-mineral interactions were evaluated by comparing K(OC) for demineralized (HF-treated) soils, with K(OC) for the corresponding whole soils. For diuron and phenanthrene, average ratios of K(OC) of the HF-treated soils to K(OC) of the whole soils were 2.5 and 2.3, respectively, indicating a substantial depression of K(OC) due to the presence of minerals in the whole soils. The effect of organic matter chemistry was determined by correlating K(OC) against distributions of C types determined using solid-state (13)C NMR spectroscopy. For diuron, K(OC) was positively correlated with aryl C and negatively correlated with O-alkyl C, for both whole and HF-treated soils, whereas for phenanthrene, these correlations were only present for the HF-treated soils. We suggest that the lack of a clear effect of organic matter chemistry on whole soil K(OC) for phenanthrene is due to an over-riding influence of organic matter-mineral interactions in this case. This hypothesis is supported by a correlation between the increase in K(OC) on HF-treatment and the soil clay content for phenanthrene, but not for diuron.

  14. Peptide π-Electron Conjugates: Organic Electronics for Biology?

    Science.gov (United States)

    Ardoña, Herdeline Ann M; Tovar, John D

    2015-12-16

    Highly ordered arrays of π-conjugated molecules are often viewed as a prerequisite for effective charge-transporting materials. Studies involving these materials have traditionally focused on organic electronic devices, with more recent emphasis on biological systems. In order to facilitate the transition to biological environments, biomolecules that can promote hierarchical ordering and water solubility are often covalently appended to the π-electron unit. This review highlights recent work on π-conjugated systems bound to peptide moieties that exhibit self-assembly and aims to provide an overview on the development and emerging applications of peptide-based supramolecular π-electron systems.

  15. What are Contaminants of Emerging Concern (CECs) ?Examples of Biological and Chemistry Approaches to their Detection, Exposure and Effects?

    Science.gov (United States)

    This presentation will overview what Contaminants of Emerging Concern (CECs) are, provide some examples of various CECs and some of the biological and chemistry approaches to assess their exposure and effects to aquatic life. The term CECs has been used since the 1990s to identif...

  16. Biological Chemistry and Functionality of Protein Sulfenic Acids and Related Thiol Modifications

    Science.gov (United States)

    Devarie-Baez, Nelmi O.; Silva Lopez, Elsa I.; Furdui, Cristina M.

    2016-01-01

    Selective modification of proteins at cysteine residues by reactive oxygen, nitrogen or sulfur species formed under physiological and pathological states is emerging as a critical regulator of protein activity impacting cellular function. This review focuses primarily on protein sulfenylation (-SOH), a metastable reversible modification connecting reduced cysteine thiols to many products of cysteine oxidation. An overview is first provided on the chemistry principles underlining synthesis, stability and reactivity of sulfenic acids in model compounds and proteins, followed by a brief description of analytical methods currently employed to characterize these oxidative species. The following chapters present a selection of redox-regulated proteins for which the -SOH formation was experimentally confirmed and linked to protein function. These chapters are organized based on the participation of these proteins in the regulation of signaling, metabolism and epigenetics. The last chapter discusses the therapeutic implications of altered redox microenvironment and protein oxidation in disease. PMID:26340608

  17. Research on condensed matter and atomic physics using major experimental facilities and devices: Physics, chemistry, biology. Reports on results. Vol. 3. 4. Chemistry. 5. Biology. 6. Development of methods and instruments

    International Nuclear Information System (INIS)

    1993-01-01

    This report in three volumes substantiates the contents of the programme survey published in September 1989. The progress reports cover the following research areas: Vol. I, (1). Atomic and molecular physics - free atoms, molecules, macromolecules, clusters, matrix-isolated atoms and molecules. (2) Physics and chemistry of surfaces and interfaces - epitaxy, surface structure, adsorption, electrical, magnetic, and optical properties, thin films, synthetic layer structure. Vol. II, (3). Solid-state physics, and materials science -structural research, lattice dynamics, magnetic structure and dynamics, electronic states; load; spin and pulse density fluctuations; diffusion and internal motion, defects, unordered systems and liquids. Vol. III, (4). Chemistry - bonding and structure, kinetics and reaction mechanisms, polymer research, analysis and synthesis. (5). Biology, - structure and dynamics of biological macromolecules, membrane and cell biology. (6) Development of methods and instruments - neutron sources, synchrotron sources, special accelerators, research with interlinked systems and devices. (orig.) [de

  18. #IHeartChemistryNCSU: Free Choice, Content, and Elements of Science Communication as the Framework for an Introductory Organic Chemistry Project

    Science.gov (United States)

    Frohock, Bram H.; Winterrowd, Samantha T.; Gallardo-Williams, Maria T.

    2018-01-01

    Students in a large introductory organic chemistry class were given the freedom to choose an organic compound of interest and were challenged to develop an educational object (physical or digital) designed to be shared with the broader public via social media. Analysis of the project results shows that most students appreciated the open nature of…

  19. "No one does this for fun": Contextualization and process writing in an organic chemistry laboratory course

    Science.gov (United States)

    Gay, Andrea

    This study investigated the introduction of curriculum innovations into an introductory organic chemistry laboratory course. Pre-existing experiments in a traditional course were re-written in a broader societal context. Additionally, a new laboratory notebook methodology was introduced, using the Decision/Explanation/Observation/Inference (DEOI) format that required students to explicitly describe the purpose of procedural steps and the meanings of observations. Experts in organic chemistry, science writing, and chemistry education examined the revised curriculum and deemed it appropriate. The revised curriculum was introduced into two sections of organic chemistry laboratory at Columbia University. Field notes were taken during the course, students and teaching assistants were interviewed, and completed student laboratory reports were examined to ascertain the impact of the innovations. The contextualizations were appreciated for making the course more interesting; for lending a sense of purpose to the study of chemistry; and for aiding in students' learning. Both experts and students described a preference for more extensive connections between the experiment content and the introduced context. Generally, students preferred the DEOI method to journal-style laboratory reports believing it to be more efficient and more focused on thinking than stylistic formalities. The students claimed that the DEOI method aided their understanding of the experiments and helped scaffold their thinking, though some students thought that the method was over-structured and disliked the required pre-laboratory work. The method was used in two distinct manners; recursively writing and revising as intended and concept contemplation only after experiment completion. The recursive use may have been influenced by TA attitudes towards the revisions and seemed to engender a sense of preparedness. Students' engagement with the contextualizations and the DEOI method highlight the need for

  20. Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

    Full Text Available The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.

  1. Redox chemistry and natural organic matter (NOM): Geochemists' dream, analytical chemists' nightmare

    Science.gov (United States)

    Macalady, Donald L.; Walton-Day, Katherine

    2011-01-01

    Natural organic matter (NOM) is an inherently complex mixture of polyfunctional organic molecules. Because of their universality and chemical reversibility, oxidation/reductions (redox) reactions of NOM have an especially interesting and important role in geochemistry. Variabilities in NOM composition and chemistry make studies of its redox chemistry particularly challenging, and details of NOM-mediated redox reactions are only partially understood. This is in large part due to the analytical difficulties associated with NOM characterization and the wide range of reagents and experimental systems used to study NOM redox reactions. This chapter provides a summary of the ongoing efforts to provide a coherent comprehension of aqueous redox chemistry involving NOM and of techniques for chemical characterization of NOM. It also describes some attempts to confirm the roles of different structural moieties in redox reactions. In addition, we discuss some of the operational parameters used to describe NOM redox capacities and redox states, and describe nomenclature of NOM redox chemistry. Several relatively facile experimental methods applicable to predictions of the NOM redox activity and redox states of NOM samples are discussed, with special attention to the proposed use of fluorescence spectroscopy to predict relevant redox characteristics of NOM samples.

  2. Organ-on-a-Chip: New Platform for Biological Analysis

    Directory of Open Access Journals (Sweden)

    Fan An

    2015-01-01

    Full Text Available Direct detection and analysis of biomolecules and cells in physiological microenvironment is urgently needed for fast evaluation of biology and pharmacy. The past several years have witnessed remarkable development opportunities in vitro organs and tissues models with multiple functions based on microfluidic devices, termed as “organ-on-a-chip”. Briefly speaking, it is a promising technology in rebuilding physiological functions of tissues and organs, featuring mammalian cell co-culture and artificial microenvironment created by microchannel networks. In this review, we summarized the advances in studies of heart-, vessel-, liver-, neuron-, kidney- and Multi-organs-on-a-chip, and discussed some noteworthy potential on-chip detection schemes.

  3. Combinatorial chemistry

    DEFF Research Database (Denmark)

    Nielsen, John

    1994-01-01

    An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds.......An overview of combinatorial chemistry is presented. Combinatorial chemistry, sometimes referred to as `irrational drug design,' involves the generation of molecular diversity. The resulting chemical library is then screened for biologically active compounds....

  4. Human Development VIII: A Theory of “Deep” Quantum Chemistry and Cell Consciousness: Quantum Chemistry Controls Genes and Biochemistry to Give Cells and Higher Organisms Consciousness and Complex Behavior

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2006-01-01

    Full Text Available Deep quantum chemistry is a theory of deeply structured quantum fields carrying the biological information of the cell, making it able to remember, intend, represent the inner and outer world for comparison, understand what it “sees”, and make choices on its structure, form, behavior and division. We suggest that deep quantum chemistry gives the cell consciousness and all the qualities and abilities related to consciousness. We use geometric symbolism, which is a pre-mathematical and philosophical approach to problems that cannot yet be handled mathematically. Using Occam’s razor we have started with the simplest model that works; we presume this to be a many-dimensional, spiral fractal. We suggest that all the electrons of the large biological molecules’ orbitals make one huge “cell-orbital”, which is structured according to the spiral fractal nature of quantum fields. Consciousness of single cells, multi cellular structures as e.g. organs, multi-cellular organisms and multi-individual colonies (like ants and human societies can thus be explained by deep quantum chemistry. When biochemical activity is strictly controlled by the quantum-mechanical super-orbital of the cell, this orbital can deliver energetic quanta as biological information, distributed through many fractal levels of the cell to guide form and behavior of an individual single or a multi-cellular organism. The top level of information is the consciousness of the cell or organism, which controls all the biochemical processes. By this speculative work inspired by Penrose and Hameroff we hope to inspire other researchers to formulate more strict and mathematically correct hypothesis on the complex and coherence nature of matter, life and consciousness.

  5. Biological and Physical Principles in Self-Organization of Brain

    Science.gov (United States)

    Kröger, H.

    2007-04-01

    Complexity is a widespread phenomenon in nature. The brain is a foremost example of complexity. We address the question: How does such complexity emerge in brain? Which are the biological, chemical or physical principles at work which organize the formation of complixity? In particular we address the topics (i) adaptive learning, (ii) neuron cell death and pruning of synaptic connection afterbirth, (iii) small world and scale free architecture of neural connectivity, (iv) feature maps and the Kohonen model, (v) self-organized criticality and 1/f frequency scaling.

  6. A spatially extensive, 25-year time series of urbanization impacts on stream chemistry and biological response

    Science.gov (United States)

    Baker, M. E.; Schley, M. L.; Martin, H. M.; Sexton, J. O.

    2013-12-01

    Over the past quarter-century, urban expansion has posed an increasingly serious threat to freshwater systems, yet most studies investigating urban impacts rely on space-for-time analysis to characterize chemical and biological responses or infer causal mechanisms. Despite a well-articulated rationale, such inference is often confounded by inability to separate gradients of urbanization from strong spatial covariates and historical legacies. Temporal analysis of monitoring can control for these covariates, but continuous urbanization data have been lacking. Thus, we know relatively little about the chemical and biological trajectories of streams during urbanization, from which to derive expectations following mitigation. We used a newly developed 25-y annual time series of 30m impervious cover (IC) encompassing the DC-Baltimore metropolitan corridor to relate urbanization patterns to long-term stream biota and water quality monitoring data in 50 watersheds from Maryland's core/trend program. We assessed seasonal chemical data (3 month average) for trends in magnitude and variation, as well as the frequency of extreme values. Stream macroinvertebrates were analyzed for taxon-specific changes in abundance and/or occurrence frequency using Threshold Indicator Taxon Analysis (TITAN), and change points were compared with shifts in both impervious surface and stream chemistry. At surprisingly low (0-3% IC) levels of watershed urbanization, we noted marked increases in measures of fall and winter dissolved material and pulses of alkalinity corresponding with increases in impervious cover. At moderate (3-8% IC) levels, we found continued correspondence between increasing impervious cover and both dissolved material and alkalinity in all seasons, and marked changes in macroinvertebrate community composition. Changes in macroinvertebrates appeared more closely associated with pulses of development than changes in monthly water chemistry. However, at higher levels of

  7. Detection of Organics at Mars: How Wet Chemistry Onboard SAM Helps

    Science.gov (United States)

    Buch, A.; Freissinet, Caroline; Szopa, C.; Glavin, D.; Coll, P.; Cabane, M.; Eigenbrode, J.; Navarro-Gonzalez, R.; Coscia, D.; Teinturier, S.; hide

    2013-01-01

    For the first time in the history of space exploration, a mission of interest to astrobiology could be able to analyze refractory organic compounds in the soil of Mars. Wet chemistry experiment allow organic components to be altered in such a way that improves there detection either by releasing the compounds from sample matricies or by changing the chemical structure to be amenable to analytical conditions. The latter is particular important when polar compounds are present. Sample Analysis at Mars (SAM), on the Curiosity rover of the Mars Science Laboratory mission, has onboard two wet chemistry experiments: derivatization and thermochemolysis. Here we report on the nature of the MTBSTFA derivatization experiment on SAM, the detection of MTBSTFA in initial SAM results, and the implications of this detection.

  8. Handbook of heterocyclic chemistry

    National Research Council Canada - National Science Library

    Katritzky, Alan R

    2010-01-01

    ... Heterocyclic Chemistry I (1984) Comprehensive Heterocyclic Chemistry II (1996) Comprehensive Heterocyclic Chemistry III (2008) Comprehensive Organic Functional Group Transformations I (1995) Compreh...

  9. Radiation damage with biological specimens and organic materials

    International Nuclear Information System (INIS)

    Glaeser, R.M.

    1979-01-01

    The radiation damage referred to in this chapter is defined as any changes in the physical structure or chemical makeup of the specimen which occur as a result of exposure to the electron beam. Radiation damage occurs in organic materials predominantly as a consequence of inelastic scattering of the incident electrons which frequently results in molecular ionization and radiolysis. Other types of radiation damage which can occur are specimen etching, which occurs as the result of synergistic action of electron irradiation and the presence of certain residual gasses, and specimen heating which occurs only at electron current densities that are large on the scale of ionization damage. The primary events in radiation physics and radiation chemistry and signal-to-noise considerations are also discussed in some detail

  10. Column chromatography with almecega resin: a project for experimental organic chemistry

    International Nuclear Information System (INIS)

    Vieira Junior, Gerardo Magela; Carvalho, Adonias Almeida; Gonzaga, Wellington de Abreu; Chaves, Mariana H.

    2007-01-01

    The use of natural products to demonstrate the silica gel column chromatography technique is proposed in the present article. It describes the separation of the triterpenes α- and β-amirin from the diol breine and maniladiol, obtained from almecega resin (Protium heptaphyllum March.). The experiment uses an accessible material, was accomplished in 4 h, and can be applied with success an the experimental course of organic chemistry for undergraduate students. (author)

  11. 'Nothing of chemistry disappears in biology': the Top 30 damage-prone endogenous metabolites.

    Science.gov (United States)

    Lerma-Ortiz, Claudia; Jeffryes, James G; Cooper, Arthur J L; Niehaus, Thomas D; Thamm, Antje M K; Frelin, Océane; Aunins, Thomas; Fiehn, Oliver; de Crécy-Lagard, Valérie; Henry, Christopher S; Hanson, Andrew D

    2016-06-15

    Many common metabolites are intrinsically unstable and reactive, and hence prone to chemical (i.e. non-enzymatic) damage in vivo Although this fact is widely recognized, the purely chemical side-reactions of metabolic intermediates can be surprisingly hard to track down in the literature and are often treated in an unprioritized case-by-case way. Moreover, spontaneous chemical side-reactions tend to be overshadowed today by side-reactions mediated by promiscuous ('sloppy') enzymes even though chemical damage to metabolites may be even more prevalent than damage from enzyme sloppiness, has similar outcomes, and is held in check by similar biochemical repair or pre-emption mechanisms. To address these limitations and imbalances, here we draw together and systematically integrate information from the (bio)chemical literature, from cheminformatics, and from genome-scale metabolic models to objectively define a 'Top 30' list of damage-prone metabolites. A foundational part of this process was to derive general reaction rules for the damage chemistries involved. The criteria for a 'Top 30' metabolite included predicted chemical reactivity, essentiality, and occurrence in diverse organisms. We also explain how the damage chemistry reaction rules ('operators') are implemented in the Chemical-Damage-MINE (CD-MINE) database (minedatabase.mcs.anl.gov/#/top30) to provide a predictive tool for many additional potential metabolite damage products. Lastly, we illustrate how defining a 'Top 30' list can drive genomics-enabled discovery of the enzymes of previously unrecognized damage-control systems, and how applying chemical damage reaction rules can help identify previously unknown peaks in metabolomics profiles. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  12. Pedagogical Content Knowledge in Organic Chemistry: A Case Study of the University Teacher

    Directory of Open Access Journals (Sweden)

    Diana Lineth Parga-Lozano

    2017-08-01

    Full Text Available From Science Education, the Pedagogical Content Knowledge (PCK is making an important contribution to the analysis of teacher training and the improvement of professionals. As such, a study was conducted to characterise the PCK of a teacher holding a degree in chemistry teaching; he teaches organic chemistry concepts at a higher education institution. The research involved a case study and was qualitative in nature; document analysis was also used as an analytical technique; besides, information was collected by use of Representations of Content (ReCo, Pedagogical and Professional Experience Repertoires (PaP-eR, document analysis of the participating teacher’s work, classroom observation, and interviews. With these tools, we were able to determine the strengths and weaknesses of the participating teacher, and from there, to infer aspects that needed improving in training undergraduates in chemistry. I found that, in this case, the teacher sees himself as chemist and not as chemistry teacher (i.e. there is a lack of professional identity; perhaps, because it is the dominant factor in his disciplinary knowledge at the expense of topics related to the knowledge of school context, as well as historical-epistemological and psycho-pedagogical knowledge. The latter indicates, as a characteristic of the participant’s PCK, that this PCK is incipient due to the disarticulation of its components, which weakens the teaching of organic chemistry concepts. This suggests the need to strengthen the initial training of teachers in their role as teaching professionals, and to integrate components of the PCK.

  13. The Clarinet Reed: AN Introduction to its Biology, Chemistry, and Physics

    Science.gov (United States)

    Casadonte, Donald Jay

    Although clarinet reeds have been used for over two-hundred years, there has been little scientific study of the reed, either from a material science or engineering perspective. This document is intended to be the first large-scale study of the clarinet reed covering its biology, chemistry and physics. The reed is made, most often, from cane--Arundo donax. We present a complete atlas of the anatomy of Arundo donax, and examine the role of each of the cellular components in the clarinet reed performance. We examine the three principal chemical components of the processed clarinet reed: cellulose, xylan, and lignin through the use of instrumental analysis. We examine the breakdown pathways of the clarinet reed, and isolate five: (1) decrystallization of the cellulose microstructure, (2) removal of xylan by saliva, (3) plasticization of the reed material due to alkalai attack in saliva, (4) the culturing of a bacterium, Staph Epidermitis, in the cell wall matrix, (5) density changes due to salival coating of the reed. The physics of the reed is examined, and a finite element model of the modal shapes is presented. We present a theoretical treatment of the two modes of excitation of the reed, a low frequency mode (normal playing mode) due to vortex shedding, and a high frequency mode which is associated with reed squeak.

  14. REDOX CHEMISTRY OF MOLYBDENUM IN NATURAL WATERS AND ITS INVOLVEMENT IN BIOLOGICAL EVOLUTION

    Directory of Open Access Journals (Sweden)

    Deli eWang

    2012-12-01

    Full Text Available The transition element molybdenum (Mo possesses diverse valances (+II to +VI, and is involved in forming cofactors in more than 60 enzymes in biology. Redox switching of the element in these enzymes catalyzes a series of metabolic reactions in both prokaryotes and eukaryotes, and the element therefore plays a fundamental role in the global carbon, nitrogen, and sulfur cycling. In the present oxygenated waters, oxidized Mo(VI predominates thermodynamically, whilst reduced Mo species are mainly confined within specific niches including cytoplasm. Only recently has the reduced Mo(V been separated from Mo(VI in sulfidic mats and even in some reducing waters. Given the presence of reduced Mo(V in contemporary anaerobic habitats, it seems that reduced Mo species were present in the ancient reducing ocean (probably under both ferrigenous and sulfidic conditions, prompting the involvement of Mo in enzymes including nitrogenase and nitrate reductase. During the global transition to oxic conditions, reduced Mo species were constrained to specific anaerobic habitats, and efficient uptake systems of oxidized Mo(VI became a selective advantage both for prokaryotic and eukaryotic cells. Some prokaryotes are still able to directly utilize reduced Mo if any exists in ambient environments. In total, this mini-review describes the redox chemistry and biogeochemistry of Mo over the Earth’s history.

  15. DNA as information: at the crossroads between biology, mathematics, physics and chemistry.

    Science.gov (United States)

    Cartwright, Julyan H E; Giannerini, Simone; González, Diego L

    2016-03-13

    On the one hand, biology, chemistry and also physics tell us how the process of translating the genetic information into life could possibly work, but we are still very far from a complete understanding of this process. On the other hand, mathematics and statistics give us methods to describe such natural systems-or parts of them-within a theoretical framework. Also, they provide us with hints and predictions that can be tested at the experimental level. Furthermore, there are peculiar aspects of the management of genetic information that are intimately related to information theory and communication theory. This theme issue is aimed at fostering the discussion on the problem of genetic coding and information through the presentation of different innovative points of view. The aim of the editors is to stimulate discussions and scientific exchange that will lead to new research on why and how life can exist from the point of view of the coding and decoding of genetic information. The present introduction represents the point of view of the editors on the main aspects that could be the subject of future scientific debate. © 2016 The Author(s).

  16. Carotenoids from Marine Organisms: Biological Functions and Industrial Applications

    Directory of Open Access Journals (Sweden)

    Christian Galasso

    2017-11-01

    Full Text Available As is the case for terrestrial organisms, carotenoids represent the most common group of pigments in marine environments. They are generally biosynthesized by all autotrophic marine organisms, such as bacteria and archaea, algae and fungi. Some heterotrophic organisms also contain carotenoids probably accumulated from food or partly modified through metabolic reactions. These natural pigments are divided into two chemical classes: carotenes (such as lycopene and α- and β-carotene that are composed of hydrogen and carbon; xanthophylls (such as astaxanthin, fucoxanthin and lutein, which are constituted by hydrogen, carbon and oxygen. Carotenoids, as antioxidant compounds, assume a key role in the protection of cells. In fact, quenching of singlet oxygen, light capture and photosynthesis protection are the most relevant biological functions of carotenoids. The present review aims at describing (i the biological functions of carotenoids and their benefits for human health, (ii the most common carotenoids from marine organisms and (iii carotenoids having large success in pharmaceutical, nutraceutical and cosmeceutical industries, highlighting the scientific progress in marine species cultivation for natural pigments production.

  17. Metal-organic frameworks for analytical chemistry: from sample collection to chromatographic separation.

    Science.gov (United States)

    Gu, Zhi-Yuan; Yang, Cheng-Xiong; Chang, Na; Yan, Xiu-Ping

    2012-05-15

    In modern analytical chemistry researchers pursue novel materials to meet analytical challenges such as improvements in sensitivity, selectivity, and detection limit. Metal-organic frameworks (MOFs) are an emerging class of microporous materials, and their unusual properties such as high surface area, good thermal stability, uniform structured nanoscale cavities, and the availability of in-pore functionality and outer-surface modification are attractive for diverse analytical applications. This Account summarizes our research on the analytical applications of MOFs ranging from sampling to chromatographic separation. MOFs have been either directly used or engineered to meet the demands of various analytical applications. Bulk MOFs with microsized crystals are convenient sorbents for direct application to in-field sampling and solid-phase extraction. Quartz tubes packed with MOF-5 have shown excellent stability, adsorption efficiency, and reproducibility for in-field sampling and trapping of atmospheric formaldehyde. The 2D copper(II) isonicotinate packed microcolumn has demonstrated large enhancement factors and good shape- and size-selectivity when applied to on-line solid-phase extraction of polycyclic aromatic hydrocarbons in water samples. We have explored the molecular sieving effect of MOFs for the efficient enrichment of peptides with simultaneous exclusion of proteins from biological fluids. These results show promise for the future of MOFs in peptidomics research. Moreover, nanosized MOFs and engineered thin films of MOFs are promising materials as novel coatings for solid-phase microextraction. We have developed an in situ hydrothermal growth approach to fabricate thin films of MOF-199 on etched stainless steel wire for solid-phase microextraction of volatile benzene homologues with large enhancement factors and wide linearity. Their high thermal stability and easy-to-engineer nanocrystals make MOFs attractive as new stationary phases to fabricate MOF

  18. Complex chemistry

    International Nuclear Information System (INIS)

    Kim, Bong Gon; Kim, Jae Sang; Kim, Jin Eun; Lee, Boo Yeon

    2006-06-01

    This book introduces complex chemistry with ten chapters, which include development of complex chemistry on history coordination theory and Warner's coordination theory and new development of complex chemistry, nomenclature on complex with conception and define, chemical formula on coordination compound, symbol of stereochemistry, stereo structure and isomerism, electron structure and bond theory on complex, structure of complex like NMR and XAFS, balance and reaction on solution, an organo-metallic chemistry, biology inorganic chemistry, material chemistry of complex, design of complex and calculation chemistry.

  19. Impacts of effluent from Carlsbad Desalination Plant on the coastal biology and chemistry - a in-situ study of pre- and post-discharge.

    Science.gov (United States)

    Petersen, K. L.; Paytan, A.; Potts, D. C.; Heck, N.

    2016-02-01

    The Carlsbad Desalination plant located by Carlsbad Beach in Southern California is currently under construction, estimated for operation in late 2015. This study is conducting in-situ measurements of the effects of the effluent discharge. Effluent will be mixed with power plant cooling water. Both pre- and post-discharge measurements of salinity, temperature, Chl a, nutrients (NO3, PO4 and silica), δ13C and δ15N stable isotopes, DOC, radioisotopes, organic pollutants, sediment sorting, algae diversity and benthic organisms' diversity are collected and compared. This allows for a real-time comparison of the effect of discharge. Pre-discharge sampling was done in the winter and summer seasons to capture seasonal variability. The first baseline results of the water chemistry pre-discharge suggest homogenous water chemistry in this coastal region at the time of sampling due to wave and tidal mixing. The outflow plume has a relative higher water temperature but other than that samples collected around the discharge site are not statistically different than around a control site. The biological samples, however, shows that the high water flow rate at the discharge channel seems to disturb benthic organisms from settling on the bottom (larger grain size and lower benthic organisms' abundance). The most abundant organisms in the area were the tube-forming worms in the genus Polychaeta. An algae count showed that at all sites sampled the diatom Pseudo-Nitzschia sp. (a known toxic alga that forms large algae blooms) is the most abundant phytoplankton. Based on the first pre-discharge data it is concluded that, beside differences in water temperature, the water chemistry is relatively uniform and corresponds to conditions expected for coastal seawater in this region at the time of sampling. However, because of the heavy water flow from the outflow channel the benthic community shows decreased abundance in the vicinity of the outflow.

  20. Synthesis of liquid crystals derived from nitroazobenzene: a proposed multistep synthesis applied to organic chemistry laboratory classes

    International Nuclear Information System (INIS)

    Cristiano, Rodrigo; Cabral, Marilia Gabriela B.; Aquino, Rafael B. de; Cristiano, Claudia M.Z.

    2014-01-01

    We describe a synthetic route consisting of five steps from aniline to obtain liquid crystal compounds derived from nitroazobenzene. Syntheses were performed during the second half of the semester in organic chemistry laboratory classes. Students characterized the liquid crystal phase by the standard melting point techniques, differential scanning calorimetry and polarized optical microscopy. These experiments allow undergraduate students to explore fundamentally important reactions in Organic Chemistry, as well as modern concepts in Chemistry such as self-assembly and self-organization, nanostructured materials and molecular electronics. (author)