Drawing chiral

A Draw chiral molecules that meet the following descriptions ... 

Draw chiral moleculci that meol the following deftcripikins ... 

Draw chiral molecules that meet the following descriptions (a) A chloroalkane, CgHnCl (b) An alcohol, C Hi40... 

This protocol presents the application of modern computer-aided modeling tools dealing with chirality - stereo drawing, chiral centers aimotation, chiral ligand docking and analysis of complexes with the receptor, chiral descriptors in QSAR, simulation of protein-DNA or DNA-DNA complexes with respect to their chirality, chiral catalysis. 

In Summary A Fischer projection is a convenient way of drawing chiral molecules. We can rotate such projections in the plane by 180° (retains absolute configuration) but not by 90° (changes absolute configuration). Switching substituents reverses absolute configuration,... 

Fischer projection A method of representing three-dimensional structures in two-dimensional drawings in which the chiral atom(s) lies in the plane of the paper. The two enantiomeric forms of glyceraldehyde are represented as... 

As represented in the wedge and dash drawing at the top of this table the molecule is already appro priately oriented Hydrogen is the lowest ranked atom attached to the chirality center and points away from us... 

Lei s relurn fo bromochlorofluoromelhane as a simple example of a chiral mole cule The Iwo enanliomers of BrClFCH are shown as ball and slick models as wedge and dash drawings and as Fischer projections m Figure 7 6 Fischer projeclions are always generated Ihe same way Ihe molecule is oriented so lhal Ihe verlical bonds al Ihe chiralily center are directed away from you and Ihe horizonlal bonds poinl toward you A projeclion of Ihe bonds onto Ihe page is a cross The chiralily center lies al Ihe center of Ihe cross bul is nol explicilly shown... 

FIGURE 7 12 Chohc acid Its 11 chirality centers are those carbons at which stereochemistry is indicated in the structural drawing at the left The molecular model at the right more dearly shows the overall shape of the molecule... 

Let s return to bromochlorofluoromethane as a simple example of a chiral molecule. The two enantiomers of BrCIFCH are shown as ball-and-stick models, as wedge-and-dash drawings, and as Fischer projections in Figure 7.6. Fischer projections are always generated the same way the molecule is oriented so that the vertical bonds at the chirality center are directed away from you and the horizontal bonds point toward you. A projection of the bonds onto the page is a cross. The chirality center lies at the center of the cross but is not explicitly shown. 

Aldoses with at least three carbons and ketoses with at least four carbons contain chiral centers (Chapter 4). The nomenclature for such molecules must specify the configuration about each asymmetric center, and drawings of these molecules must be based on a system that clearly specifies these configurations. 

C atoms are labelled a-e (see text), (b), (c) Line drawings of the two enantiomers of C76 viewed along the short C2 rotation axis and illustrating the chiral D2 symmetry of the molecule. 

Each of the molecules below (carvone, ibuprofen anc limonene) incorporates a single chiral center. Identify ii and draw both R and S forms of each. 

Drawing the Three-Dimensional Structure of a Chiral Molecule... 

Problem 9.3. Alanine, an amino acid found in proteins, is chiral. Draw the two enantiomers of ala- nine using the standard convention of solid, wedged, and dashed lines. 

Which of the following compounds are chiral Draw them, and label the chirality centers. 

A Eight alcohols have the formula CsH O. Draw them. Which are chiral ... 

Draw the nine chiral molecules that have the formula CgH Br. 

Draw the structure of a meso compound that has five carbons and three chirality centers. 

Problem 10.3 Draw and name all monochloro products you would expect to obtain from radical chlorination of 2-methylpentane. Which, if any, are chiral ... 

Draw and name the monochlorination products you might obtain by radical chlorination of 2-inethylbutane. Which of the products are chiral Are any of the products optically active ... 

Methylhexane undergoes radical bromination to yield optically inactive 3-bromo-3-methylhexane as the major product. Is the product chiral What conclusions can you draw about the radical intermediate ... 

Draw the R enantiomer of the reactant, and then change the configuration of the chirality center while replacing the Br with a CN. 

Draw the three-dimensional furanose form of ascorbic acid (Problem 25.32), and assign R or S stereochemistry to each chirality center. 

The ending caine stems from cocaine, the first clinically employed local anaesthetic. Procaine and tetracaine are ester-linked substances, the others are amides. Amide bonded local anaesthetics usually contain two i s in their name, ester-bonded only one. In the structure drawings, the lipophilic portion of the molecule is depicted at the left, the amine at the right. The asterisk marks the chiral centre of the stereoisomeric drugs. Lipid solubility is given as the logarithm of the water octanol partition coefficient, log(P). 

Draw the structures of the isomeric forms of [CrClBrI(NH3)5J. Which isomers are chiral ... 

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