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Concept: American Chemical Society

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Chemistry researchers are frequently evaluated on the perceived significance of their work with the citation count as the most commonly-used metric for gauging this property. Recent studies have called for a broader evaluation of significance that includes more nuanced bibliometrics as well as altmetrics to more completely evaluate scientific research. To better understand the relationship between metrics and peer judgements of significance in chemistry, we have conducted a survey of chemists to investigate their perceptions of previously published research. Focusing on a specific issue of the Journal of the American Chemical Society published in 2003, respondents were asked to select which articles they thought best matched importance and significance given several contexts: highest number of citations, most significant (subjectively defined), most likely to share among chemists, and most likely to share with a broader audience. The answers to the survey can be summed up in several observations. The ability of respondents to predict the citation counts of established research is markedly lower than the ability of those counts to be predicted by the h-index of the corresponding author of each article. This observation is conserved even when only considering responses from chemists whose expertise falls within the subdiscipline that best describes the work performed in an article. Respondents view both cited papers and significant papers differently than papers that should be shared with chemists. We conclude from our results that peer judgements of importance and significance differ from metrics-based measurements, and that chemists should work with bibliometricians to develop metrics that better capture the nuance of opinions on the importance of a given piece of research.

Concepts: Scientific method, Academic publishing, Research, Perception, Mind, Hypothesis, American Chemical Society, Citation impact

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A symposium entitled “Advances in Food Allergen Detection” was held at the 243rd American Chemical Society Meeting in March 2012 in San Diego, CA and was sponsored by the ACS Division of Agricultural and Food Chemistry. The purpose of the symposium was to convene the leaders in the food allergen analysis field for presentations on, and discussions of, the state of the art, new developments, and critical challenges in the detection and quantitation of allergenic proteins in foods. Twenty-five presentations were delivered by speakers representing academic, government and industrial institutions in ten countries. The presentations covered all aspects of food allergens, including a historical progress review, regulatory policies, clinical practices, food processing effects, food production equipment cross-contamination and cleaning, and the performance of several food allergen analytical strategies and technologies. This article is intended to provide a brief summary of the presentations as well as a record of the proceedings of the symposium, which was deemed a great success in advancing food allergen analysis.

Concepts: Chemistry, Food, Antigen, Allergen, Food allergy, Allergen immunotherapy, American Chemical Society

3

The authors were inspired to explore the topic of gender diversity in computational chemistry based on similar recent publications in the related fields of medicinal chemistry (1) and computational biology (2). To do so, we examined historical demographics in two different professional settings, i.e. attendance/participation at the Gordon Research Conferences on Computer-Aided Drug Design and Computational Chemistry and membership in the Computers in Chemistry division of the American Chemical Society. We conclude that female representation in computational chemistry has risen steadily over the last 40 years and likely stands around 25%, a number which appears to slightly exceed that of the neighboring fields of computer science and medicinal chemistry. It is said that “a rising tide lifts all boats” (3); here, a rising tide of women scientists is having an impact on the field. Tactics to ensure this number continues to improve are highlighted.

Concepts: Pharmacology, Bioinformatics, Chemistry, Computational chemistry, Drug design, Medicinal chemistry, Computer science, American Chemical Society

2

The publication in January 1965 of the first Woodward-Hoffmann paper ushered into organic chemistry both an explanation of the stereochemistry and “allowedness” or “forbiddenness” of concerted reaction and an impetus for untold numbers of research projects. The Stereochemistry of Electrocyclic Reactions was a breakthrough publication. In this paper, details of the collaboration between R. B. Woodward and R. Hoffmann, from when they first met to discuss the solution to the “no-mechanism problem” to the date their first paper was received in the offices of the Journal of the American Chemical Society will be discussed and analyzed. The primary focus will be on the historically-relevant extant documents from the early 1960s. These include Hoffmann’s laboratory notebooks describing his research, including his extended Hückel calculations used to explain and predict the stereochemistry of electrocyclic reactions. Drafts of the Stereochemistry of Electrocyclic Reactions paper, letters, and notes by Woodward, Jerome Berson, and others will further illuminate the development of this first Woodward-Hoffmann paper.

Concepts: Scientific method, Chemical reaction, Quinine, Chemistry, 2007, American Chemical Society, 1904, 1965

2

The availability of structures and linked bioactivity data in databases is powerfully enabling for drug discovery and chemical biology. However, we now review some confounding issues with the divergent expansions of public and commercial sources of chemical structures. These are not only associated with expanding patent extraction but also increasingly large vendor collections amassed via different selection criteria between the Chemical Abstracts Service (CAS) SciFinder® and major public sources such as PubChem, ChemSpider, UniChem and others. These increasingly massive collections may include both real and virtual compounds, as well as so-called prophetic compounds from patents. We address a range of issues raised by the challenges faced resolving the NIH probe compounds. In addition we highlight the confounding of prior-art searching by virtual compounds which could impact the composition of matter patentability of a new medicinal chemistry lead. Finally, we propose some potential solutions.

Concepts: Chemistry, Patent, American Chemical Society, Chemical database, PubChem, Chemical Abstracts Service, ChemSpider, Chemical databases

0

Ronald Breslow, Samuel Latham Mitchill Professor of Chemistry at Columbia University, passed away on October 25, 2017, at the age of 86. Breslow made remarkable contributions to the fields of physical-organic and bioorganic chemistry, including biological and biomimetic transformations, and the use of molecular recognition to control reaction selectivity.

Concepts: Molecular biology, Chemical reaction, Chemistry, American Chemical Society, Columbia University faculty, Samuel Latham Mitchill

0

Sharing capital ideas: The 2017 Frontiers in Medicinal Chemistry (FiMC) conference, organized jointly by the German Chemical Society, the German Pharmaceutical Society, and the Swiss Chemical Society, was held at the Department of Chemistry and Biochemistry of the University of Bern in February 2017. Herein we summarize the many conference highlights, and look forward to the next FiMC meeting, to be held in Jena (Germany) in March 2018.

Concepts: European Union, Chemical reaction, Chemistry, Germany, Switzerland, American Chemical Society, Albert Einstein, Bern

0

A symposium entitled “Public Health Perspectives of Mycotoxins in Food” was held at the 251st American Chemical Society Meeting in March 2016 in San Diego, CA and was sponsored by the ACS Division of Agricultural and Food Chemistry. The purpose of the symposium was to convene the leading mycotoxin researchers throughout the world to discuss the current state of knowledge as well as research needs with respect to evaluating the toxicological properties of mycotoxins, and ways to detect, control and reduce human and animal exposure to these natural toxins. Twenty-three presentations were delivered by speakers representing academic, government and industrial institutions from North America, Europe, Asia and Africa. The presentations covered such diverse topics as a historical perspective on the discovery of the major fungal toxins, occurrence of mycotoxins in food and feed, toxicological properties of mycotoxins and their influence on public health, analytical methods for mycotoxins, pre- and post-harvest control of mycotoxins, and regulatory aspects. This article is intended to provide a brief summary of the presentations as well as a record of the proceedings of the symposium.

Concepts: Fungus, Chemistry, Mycotoxin, California, American Chemical Society, Plato, Academic conference

0

The Frenkel exciton model is a useful tool for theoretical studies of multi- chromophore systems. We recently showed that the exciton model could be used to coarse-grain electronic structure in multichromophoric systems, focusing on singly-excited exciton states [Acc. Chem. Res. 2014, 47, 2857-2866]. However, our previous implementation excluded charge-transfer excited states, which can play an important role in light-harvesting systems and near-infrared optoelectronic materials. Recent studies have also emphasized the significance of charge-transfer in singlet fission, which mediates the coupling between the locally excited states and the multi-excitonic states. In this work, we report on an ab initio exciton model that incorporates charge-transfer excited states, and demonstrate that the model provides correct charge-transfer excitation energies and asymptotic behavior. Comparison with TDDFT and EOM-CC2 calculations shows that our exciton model is robust with respect to system size, screening parameter, and different density functionals. Inclusion of charge-transfer excited states makes the exciton model more useful for studies of singly excited states, and provides a starting point for future construction of a model that also includes double-exciton states.

Concepts: Photon, Quantum mechanics, Atom, Semiconductor, Exciton, Excited state, Yakov Frenkel, American Chemical Society

0

As therapeutic tools, diterpenes and their derivatives have gained much attention of the medicinal scientists nowadays. It is due to their pledging and important biological activities. This review congregates the anticancer diterpenes. For this, a search was made with selected keywords in PubMed, Science Direct, Web of Science, Scopus, The American Chemical Society and miscellaneous databases from January 2012 to January 2017 for the published articles. A total 28, 789 published articles were seen. Among them, 240 were included in this study. More than 250 important anticancer diterpenes and their derivatives were seen in the databases, acting in the different pathways. Some of them are already under clinical trials, while others are in the nonclinical and/or pre-clinical trials. In conclusion, diterpenes may be one of the lead molecules in the treatment of cancer. Copyright © 2017 John Wiley & Sons, Ltd.

Concepts: DNA, Medicine, Cancer, Oncology, Chemistry, Academic publishing, Medical cannabis, American Chemical Society