TIGER

Other Resources: 22 results
Properties of Alkanes  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Chirality / Optical Activity
Collection of Chiral Drug, Pesticide, and Fragrance Molecular Models  William F. Coleman
The article by Mannschreck, Kiessewetter, and von Angerer on the differential interactions between enantiomers and biological receptors (1) is the source for this month's Featured Molecules. Included in the molecule collection are all of the molecules described in the paper. In many instances we have included structures of multiple optical isomers of the same molecule so that students can not only see the forms that are active, but those that are less active, inactive, or act in an undesirable manner. These molecules will serve as good practice in determining optical configurations, and will also introduce additional forms of isomerism that students may be less familiar with than they are with R and S. Since multiple enantiomers and diastereomers are provided, students may use these molecules, together with an appropriate computational package, to verify that enantiomers have the same energy while diastereomers do not. The tuberculosis drug ethambutol provides an interesting case as both nitrogen atoms are also chiral as well as the two chiral carbon atoms. A calculation on a given structure will include the effect of that nitrogen chirality, although nitrogen inversion is expected to be quite rapid in this molecule. The conformations for the ethambutol molecules that are included here consider all four chiral atoms and are of the form (CNNC). A reasonable computational exercise would be to find the transition state for nitrogen inversion and the barrier height for that process. The supplemental material that is included with the featured article (1) includes a number of molecules that we will add to the collection as time permits. The result, including enantiomers and diastereomers, will be well over 200 additional molecules. A notice will appear in the JCE Featured Molecules column when this new set of molecules is available in JCE Online.
Chirality / Optical Activity |
Biosignaling
Stereochemistry Tutorial  Nicola Burrmann
Master the concepts organic stereochemistry with this interactive tutorial. It includes definitions, different three dimensional representations, assigning priorities to stereocenters, and determining the stereochemical relationship between molecules. Each section is followed by a question set that tests knowledge and understanding.
Stereochemistry |
Chirality / Optical Activity
The Amino Acids  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Amino Acids |
Chirality / Optical Activity
The Chemistry of Coffee  William F. Coleman
The paper Our Everyday Cup of Coffee: The Chemistry behind Its Magic by Marino Petracco provides a hearty blend of molecules for this month. The author deals with coffee at a number of different levels ranging from the economic and social to the still perplexing questions of flavor and aroma. The associated molecules demonstrate a range of structural features that students will benefit from examining in three dimensions.
Bioorganic Chemistry
Molecular Model of Tubocurarine  William F. Coleman
Curare, the Karib name for the plant from which this molecule is derived, is used in traditional South American medicine and hunting because it is a muscle relaxant. The three papers by Brunsvold and Ostercamp (1, 2, 3) provide us with an abundance of candidates for Featured Molecules this month. All of the major compounds highlighted in the papers, and many of the intermediates in the synthetic schemes, have been added to our collection. Students should note the structural similarities of the various barbiturate species and of the steroid-based compounds, as well as the interesting proto-cage structure of curare. Careful examination of the conformation of the alkyl groups in various of the molecules, when looked at as Newman projections, should convince students that their expectations about staggering substituents on adjacent tetrahedral-like carbon atoms are met in the computations. However, they should also be aware that recent work casts some doubt on the traditional explanation for that staggering (1). Charged species are presented in the collection in ionic form, without counterions (those are given in the papers), and all species except curare and atricurium besylate (molecule 40 in the third paper) were optimized at either HF/631-G(d) or B3LYP/631-G(d). The latter two molecules were optimized using HF/STO-3.
Bioorganic Chemistry
ChemPaths 104 M Feb 14  John W. Moore
Today in Chem 104: * Lecture: Review for Exam I (email questions or topics for discussion during the review session to Prof. Moore by 9am today) * No assigned reading for today. * Exam I on Wednesday Feb 16: Covers material through Feb 11; Biomolecules tutorials, Molecular Structure, Aspirin, and Biodiesel Labs.
Bioorganic Chemistry
The Elements of Life  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Bioorganic Chemistry
Carbon Compounds  
Volume 03, issue 13 of a series of leaflets covering subjects of interest to students of elementary chemistry distributed in 1929 - 1932.
Bioorganic Chemistry |
Alkanes / Cycloalkanes
Organic Compounds of Carbon  
Volume 04, issue 13 of a series of leaflets covering subjects of interest to students of elementary chemistry distributed in 1929 - 1932.
Bioorganic Chemistry |
Alkanes / Cycloalkanes
Carbon and Its Organic Compounds  
Volume 05, issue 13 of a series of leaflets covering subjects of interest to students of elementary chemistry distributed in 1929 - 1932.
Bioorganic Chemistry |
Alkanes / Cycloalkanes
Earth's Oldest Fossils  Ed Vitz
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Bioorganic Chemistry |
Geochemistry
Properties of Organic Compounds and Other Covalent Substances in Astronomy  Robert Hetue
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Bioorganic Chemistry |
Astrochemistry
Ketosis in Biology  Robert Hetue
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Aldehydes / Ketones |
Metabolism |
Bioorganic Chemistry
Molecular Models of Plant Hormones  William F. Coleman
The paper "Synthesis of Plant Auxin Derivatives and Their Effects on Ceratopteris richardii" by Corey E. Stilts and Roxanne Fisher describing an experiment begun in the organic labs and completed in a biochemistry cell biology lab provides the featured molecules for this month. The molecules in Figure 1 of that paper have been added to the collection. There is nothing particularly surprising about their structures, but students might be interested in seeing whether they can determine any structure/regulating effect relationships as the number of synthesized auxin derivatives grows. Additionally, students with little or no biochemistry background might wish to explore other systems that act as growth regulating hormones in plants, as an introduction to the variety of molecular structures that can display such bioactivity. Such molecules range from the very simple, ethene, to the adenine-derived cytokinins (an example of which, zealtin, is shown here) and the brassinosteroids. Brassinolide, a commonly occurring brassin, is also shown. These latter two structures have also been added to the molecule collection. All of the structures have been optimized at the HF/6-31G(d) level.
Synthesis |
Biological Cells |
Hormones |
Bioorganic Chemistry
Enzyme Activity as a Function of pH  Paul Krause
A matched pair of documents providing an introduction to the role of pH in the regulation of enzyme activity. The tutorial document contains all the equations and graphs for students to use to study the role of pH in enzyme kinetics. In the EnzymeExercise twin document all quations are omitted so that students can develop these interactively. The Exercise document is also ideal for display during lecture where the ideas can be developed interactively with the class as a whole.
Enzymes
Biomolecules (Netorials)  Rachel Bain, Mithra Biekmohamadi, Liana Lamont, Mike Miller, Rebecca Ottosen, John Todd, and David Shaw
Biomolecules: this is a resource in the collection "Netorials". This set of modules will provide you with a descriptive overview of the four major classes of biomolecules found in all living organisms: carbohydrates, lipids, proteins, and nucleic acids. The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Thermodynamics, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.
Bioorganic Chemistry |
Carbohydrates |
Nucleic Acids / DNA / RNA |
Lipids |
Proteins / Peptides
Catalysis in Biology  Tim Wendorff
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Catalysis |
Enzymes
ChemPaths 104 M Feb 28  John W. Moore
Today in Chem 104: * Lecture: Catalysis * Reading: Kotz, Ch. 15, Sec. 6 Moore, Ch. 13, Sec. 8-10 * Homework #6 due by 11:55 pm F Mar 4 * Biomolecules Tutorial: Enzymes (and Enzymes Quiz) due at 11:55 pm, W Mar 2.
Catalysis |
Enzymes
Increasing the Rate of a Reaction  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Catalysis |
Enzymes
Proteins  Ed Vitz, John W. Moore
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Proteins / Peptides |
Enzymes
Netorials  
The Netorials cover selected topics in first-year chemistry including: Chemical Reactions, Stoichiometry, Intermolecular Forces, Acids & Bases, Biomolecules, and Electrochemistry.
Acids / Bases |
Stoichiometry |
Proteins / Peptides |
Enzymes |
Carbohydrates |
Nucleic Acids / DNA / RNA |
Lipids |
Oxidation / Reduction |
Noncovalent Interactions