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Molecules that relate to each other where an object and its mirror image are not superimposable are called chiral (from Greek word cheiro, meaning "hand"); that is, they are like a pair of hands. These molecules also are called enantiomers. Major differences in biological activity have been observed in chiral molecules. The difference in spatial arrangements. of atoms in a molecule (that is, its stereochemistry) can influence its pharmacological, metabolic, or toxicologic activity. This is why regulatory requirements in the pharmaceutical industry demand detailed investigations of chiral molecules. Before initiating method development, it is important to develop a basic understanding of stereochemistry (1-5). Basic information on stereochemistry is provided in this article to help readers develop better understanding of the separation mechanisms that come into play in various separation methods used for chiral compounds. This knowledge can allow readers to select a desirable chiral separation method, based upon the molecular structure of the chiral compound of interest. Logical reasons for the selection process are discussed later in this article. [ABSTRACT FROM AUTHOR]

The article offers information relevant to high pressure liquid chromatography (HPLC) method development for chiral drugs. It provides basic information on stereochemistry to help readers gain better understanding on separation mechanisms that arise in different chiral compounds separation methods. It suggests a fast approach to chiral stationary phase (CSP) selection.

The article presents an interview of David Bish, professor emeritus at Indiana University about X-ray diffraction (XRD) techniques. Topics discussed include new software program, ClayStrat, which is based on a modified matrix methodology that reduces the number of matrix operations; effectiveness of XRD for probing the nature of clay minerals and other nanocrystals; and advantages of using a virtual profile to understand the nature of stacking disorders in natural and synthetic clays.

Previews the 40th EUCHEM Conference on Stereochemistry in Lucerne, Switzerland. Overview of how the conference developed; Suggestion that the program encompasses mainstream organic chemistry disciplines as well as molecular biology, molecular medicine, biophysics and materials design; Highlights of the previous conference.

Despite the unrelenting pace of research in catalytic asymmetric chemistry, relatively few catalytic enantioselective processes are currently operated on a commercial scale. Until more bio- and chemocatalytic chiral routes are developed that are robust and cost-effective for large-scale production, the bulk of optically pure compounds will have to be prepared through traditional chemistry, including conventional syntheses based on chiral substrates or stoichiometric chiral induction and separations, such as chromatographic resolutions.

Focuses on the direction of the future of synthetic organic chemistry. Concern over the serious aging of funded researchers; Importance of the asymmetric synthesis of chiral compounds in the field; Research on the synthesis of bioactive compounds.

Reports on the commemoration of discovery of the tetrahedral coordination geometry of carbon. Ramifications of the theory proposed by Jacobus Henricus van't Hoff in 1874; Contributions of the theory to the field of stereochemistry.

The article reports on the structural misassignment that was uncovered in marine toxin azaspiracid. Topics mentioned include the correction by researchers at Ohio State University on the study conducted in 1990s, the focus on correcting the stereochemistry of the cause of shellfish food poisoning, and the use of liquid chromatography in comparing the newly synthesized toxin with the authentic sample.

The article discusses the synthetic methodology for the structures of baulamycins A and B. Particular focus is given to the stereochemistry of the natural compounds and the Nuclear magnetic resonance spectroscopy of the molecules. Also included are the method led by Varinder K. Aggarwal, the use of the computational method, and the isomers in the research.

The article discusses the technique developed by Omar M. Yaghi, Seungkyu Lee, and Eugene A. Kapustin of University of California, Berkeley, as of late August 2016 to reliably examine the absolute stereochemistry of a molecule's structure. The method involves the use of aluminum atoms, which are covalently linked to the chiral framework called MOF-520. The method was successfully used in primary alcohols, phenols, vicinal diols, and carboxylic acids.

The article reports that researchers have devised a synthesis of α-amanitin, a bicyclic octapeptide produced by the death-cap mushroom, which is one of the deadliest known peptide toxins. Topics discussed include key challenges in the synthesis including making 6-hydroxy-tryptathionone cross-link that could easily form an unwanted oxindole and forming a sulfoxide with the correct stereochemistry.

The article offers information on the study conducted by researchers from the Ohio State University led by Craig J. Forsyth where they synthesized and corrects the stereochemistry of the azaspiracid-3.

Determination of the beer bitterness by measuring the contents of isohumulones in untreated beer--as fast as possible, including sample preparation, HPLC separation, and result evaluation. Furthermore, the ap-plication has to be robust and must provide reproduc-ible results, increased lifetime of the analytical column, and provide a fingerprint or characteristic pattern of the eis- and transratios. [ABSTRACT FROM AUTHOR]

Determination of the beer bitterness by measuring the contents of isohumulones in untreated beer--as fast as possible, including sample preparation, HPLC separation, and result evaluation. Furthermore, the application has to be robust and must provide reproducible results, increased lifetime of the analytical column, and provide a fi ngerprint or characteristic pattern of the cis- and trans-ratios. [ABSTRACT FROM AUTHOR]

The article offers information about superatoms, a cluster of atoms with some properties of elemental atoms. It informs that some superatoms of aluminium exhibit atomic orbital behaviour, a mathematical function that describes the wave-like behavior electrons in an atom. It also mentions that inorganic superatoms have the ability to catalyze certain reactions.

The article discusses a symposium that highlights the work of Saul Winstein in the field of organic chemistry that was held at the University of California, Los Angeles. It refers to his research on investigation of ion pairs formed during substitution reactions. It discusses explanation given by Winstein on prediction of stereochemistry of chemical components during chemical reactions.

The article reports on a study that applied highly reactive monoaryloxide-pyrrolyde (MAP) olefin metathesis catalysts to couple terminal olefins to produce the Z-alkene. The coupled terminal olefins gave Z-stereochemistry as high as 98 percent yield of resulting alkenes. It adds that it is the first time that Z-isomers of homocoupled acylic products are formed with high percentage. It cites that Z-selectivity was associated to the steric influence of the catalyst's large aryloxide ligand.

The article presents the use of supercritical fluid chromatography (SFC), with its speed, efficiency , and cost-effective for the separation and quantification of stereoisomers. It notes that SFC has been useful in separating optical isomers such as enantiomers and diastereoisomers but has a limited scope on the applications on (E)-(Z) isomers. A case study is presented in employing SFC to profile the (E)-(Z) transformation and the simultaneous resolution of the four isomers.

Several letters to the editor are presented in response to the article concerning the death of scientist Ernest L. Eliel and his contributions to the study of stereochemistry.

The article focuses on residual dipolar couplings (RDCs), a nuclear magnetic resonance (NMR) parameter, to determine stereochemical details of small molecules. RDCs offer information over the length of the entire molecule and are not limited to the short-distance relationships that are observed in standard NMR parameters such as nuclear Overhauser effects. However, not many organic chemists are using RDCs for structural determination of small molecules.

The article reports on the James Flack Norris Award in Physical Organic Chemistry given to Ben L. Feringa, a professor in molecular sciences at the University of Groningen in Netherlands. He is awarded for his work in stereochemistry, particularly for the design and synthesis of molecular motors and other nanodevices.

Focuses on researchers' discovery of a rhythmic stereochemical inversion in supramolecular system. Phenomenon called chiroptical rhythmicity; Formation of tight ion pairs between the ligand-receptor complex and the membrane surface.

The article discusses research related to assembly-line reaction by chemists including Varinder K. Aggarwal at the University of Bristol, England, published in the periodical "Nature" in 2014. Topics discussed include synthesis of polyketide natural products via an assembly-line process, development of carbon chains by repeated homologation of a carbon-boron bond using of boronic ester and an organolithium compound and stereochemistry of the methyl groups.

The article reports that a team led by researcher Makoto Fujita has reported that structural determination technique that uses crystalline sponges is inaccurate to identify stereochemistry of the compound Miyakosyne A and mentions that the technique is not useful for crystallize compounds.

The article discusses the chemistry of configuration of an alcohol's central carbon as the compound is transformed into an isonitrile and mentions that reaction allows chemists to invert stereochemistry while transforming tertiary carbon-oxygen bonds into tertiary alkyl bond with nitrogen.

The article presents information on the stereochemical complexity created by the dual catalysis for making complex molecules, such as pharmaceuticals and agrochemicals. It informs that the procedure involves the use of two catalysts to activate two starting materials, resulting in the generation of one or two stereocenters. It further informs that one of the limitations on this strategy is that the catalysis works well with only one catalyst.

The article focuses on the study that determines the molecular structure that can be applied in nanoscale scaffolds through X-ray crystallography. It states that in X-ray crystallography, X-rays are shot by a single crystal of a compound where it reveals the structure of the molecule that makes up the crystal. It mentions that the techniques was also helpful for scientist to identify the compound's stereochemistry and in protein analysis.

The article focuses on the stereochemistry of the natural products and its role in killing the cells such as lomaiviticin A, an anticancer agent. It is known that they have complex and unusual structures including two diazofluorene and several carbohydrate groups. It informs that the DNA-cleaving properties, superior cytotoxicity and symmetric structure of lomaiviticin A provides the mode of double-stranded DNA cleavage, reminiscent of antibiotics.

A response by Michael Matson to a letter to the editor about an article on terminology of stereochemistry in the June 6, 2011 issue is presented.

The article discusses new findings by researchers at the Monash University in Australia, who claim that aluminum metal atoms are arranged in a tetrahedral manner, which explains some of the mineral's properties in a better way, as opposed to viewing them as mere ions in a dynamic field of electrons.

The article presents a study which examines the chance of chiral organic molecules to undergo atmospheric reactions with ozone depending on its stereochemistry. The study accumulates quinuclidine diastereometers on silica layers and probes the model compounds' charges of ozonolysis with a spectroscopy method. Conclusion shows that chiral organic molecules can be used to discern between biogenic and anthropogenic sources of organic carbon emissions.

Several corrections to the articles including landfill projects will keep methane that was published in March 23, administration of multiple sclerosis drug copaxone published in March 6 and incorrect display of stereochemistry of domoic acid published in April 27 issues are presented.

Supercritical Fluid Chromatography (SFC) is quickly becoming a popular choice by chromatographers for analytical and preparative separations. [ABSTRACT FROM AUTHOR]

The article highlights a simple amino-acid-based catalyst that can add a silyl protecting group to one of two hydroxyl groups in a symmetric diol. Developed by chemistry professors Amir H. Hoveyda and Marc L. Snapper at Boston College in Massachusetts, the procedure can protect one of the two very similar secondary alcohol groups in such achiral diols to yield chiral products. The method is also unique in organic synthesis.

The article offers information about a study on the determination of absolute configuration of chiral molecule, which an important step in any field related to chirality as in the pharmaceutical industry. In the pharmaceutical industry, the phenomenon of chiral recognition makes it a necessity to know the absolute configuration not only of the final molecule but as early in the process of development as possible.

The article offers observations on the developments in optical lithography. The author cites the optical innovations that seemed to take us to 100nm resolution. He says that at the 32nm node and beyond, some paradigms are needed to be changed. He cites extreme-utraviolet as the consensus option for chips made in large quantities for generations beyond 32nm.

The article reports on the development of a new model for the evolution of biological homochirality by Donna G. Blackmond of Imperial College. The new model shows that amino acid–catalyzed aldol reactions provide an efficient mechanism for asymmetric amplification for single–enantiomer products. The new mechanism involves an equilibrium process that can operate in aqueous systems.

The article focuses on the successful synthesis of a compound composed of six indium atoms arranged in a linear chain, in reference to the study conducted by the researchers in England. The study broadens the understanding of main-group metal chemistry and may lead to novel strategies for preparing inorganic oligomers and polymers. According to Michael S. Hill, one of the researchers, the result of the study was surprising but completely reproducible.

The article presents a research from the Tokyo Metropolitan University which shows that stereo-array isotope labeling (SAIL) can be used in determining the structure of a 41-kDa protein. Researchers are trying to fully automate SAIL-based structure determination and to push the technique's molecular weights. It is anticipated that SAIL is going to have impact on structural protein nuclear magnetic resonance spectrometry studies.

Focuses development of the asymmetric Biginelli reaction by Chengjian Zhu and coworkers at Nanjing University in China. Capabilities of the asymmetric Biginelli reaction; Catalysts of the asymmetric Biginelli reaction; Industrial applications of the asymmetric Biginelli reaction.

Reports on the possibility of using chirality as an intrinsic property for detecting proteins on microarrays developed by John Conboy and Matthew A. Kriech at the University of Utah using second harmonic generation microscopy to take a direct image of chiral molecules.

Reports on Produits Chimiques Auxiliaires et de Synthese's (PCAS) long-time partnership with Gerard Coquerel, a chemistry professor at the University of Rouen in France. Collaboration that is focused on polymorphism and crystallization in chiral chemistry; Claim of PCAS to have carved a distinct niche in the competitive field of chiral active pharmaceutical ingredients.

Assesses the accurate theoretical description of the reaction of a hydrogen atom with methane. Increase of power of modern theoretical and computational chemistry; Evaluation of quantum dynamics simulation of the six-atom reaction; Examination of the rates for six-atom reaction.

Reports that researchers at Rutgers University have used spirodiepoxide to synthesize proteasome inhibitor epoxomicin. Role of nucleophiles in opening the spirodiepoxide rings; Generation of molecules with multiple functional groups and tailored stereochemistry; Structure of spirodiepoxide.

Reports on the finding that the stereochemistry at a chiral center at one end of a rigid molecule can influence the stereochemistry at another chiral center up to 22 bonds away, almost twice the distance previously achieved in a synthetic system. Transmission of information in a variety of chemical and biological systems; Use of amide-substituted xanthenes as the backbone of the communicative systems; Modification of a single xanthene by condensing an ephedrine molecule with an aldehyde attached to one side of the xanthene.

The article presents a calendar of upcoming events related to chemical industry. The Tetrahedron Symposium 2004 is going to be held on June 18 in New York City. From June 20-25, Gordon Research Conference on stereochemistry is going to be held in Newport. The 16th International Symposium on chirality is going to be held from July 11-14. The 10th Belgian Organic Synthesis Symposium is going to take place from July 12-16. The other 7th International Symposium on laboratory automation in process development will take place from September 23-24.

Reports on a reversible, photoresponsive, self-assembling system in which chiral information is exchanged between molecular and supramolecular units. Self-assembly of the molecules to form fibers of one particular helicity.

Reports that Edwin Vedejs has been given the 2004 Herbert C. Brown Award for Creative Research in Synthetic Methods by the American Chemical Society. Moses Gomberg Professor of Chemistry at the University of Michigan, Ann Arbor; Career as a synthetic chemist; Contributions to methodology, stereochemistry and organic synthesis.

Report on a revision in the stereochemistry of the anticancer product kahalalide F, a marine-derived cyclic depsipeptide. Determination by Isabelle Bonnard and coworkers at the University of Illinois, Urbana-Champaign and by PharmaMar of the Val-3 and Val-4 of kahalalide F to be D and L.