To be FAIR, data has to be not only Findable and Accessible, but straightforwardly Interoperable. One of the best examples of interoperability in chemistry comes from the domain of quantum chemistry. This strives to describe a molecule by its electron density distribution, from which many interesting properties can then be computed. The process is split into two parts: Computation of the wavefunction.

The annual “molecule of the year” results for 2021 are now available … and the winner is Infinitene .[cite]10.33774/chemrxiv-2021-pcwcc[/cite],[cite]10.1021/jacs.1c10807[/cite] This is a benzocirculene in the form of a figure eight loop (the infinity symbol), a shape which is also called a lemniscate [cite]10.1021/jo801022b[/cite] after the mathematical (2D) function due to Bernoulli.

In the previous post, I showed some of the diverse “non-classical“interactions between Biotin and a protein where it binds very strongly. Here I take a look at two of these interactions to discover how common they are in small molecule structures.

The title comes from the abstract of an article[cite]10.1021/acs.jmedchem.1c00975[/cite] analysing why Biotin (vitamin B7) is such a strong and effective binder to proteins, with a free energy of (non-covalent) binding approaching 21 kcal/mol.

Earlier this year, Molnupiravir hit the headlines as a promising antiviral drug. This is now followed by Paxlovid, which is the first small molecule to be aimed by design at the SAR-CoV-2 protein and which is reported as reducing greatly the risk of hospitalization or death when given within three days of symptoms appearing in high risk patients. The Wikipedia page (first created in 2021) will display a pretty good JSmol 3D model of this;

The previous post described the fascinating 170-year history of a crystalline compound known as Herapathite and its connection to the mechanism of the Finkelstein reaction via the complex of Na ⁺ I ₂ ^– (or Na ₂ ²⁺ I ₄ ^2- ). Both compounds exhibit (approximately) linear chains of iodine atoms in their crystal structures, a connection which was discovered serendipitously.

On October 13, 2021, the historical group of the Royal Society of Chemistry organised a symposium celebrating ~150 years of the history of (molecular) chirality. We met for the first time in person for more than 18 months and were treated to a splendid and diverse program about the subject. The first speaker was Professor John Steeds from Bristol, talking about the early history of light and the discovery of its polarisation.

In the previous blog post, I looked at the metadata records registered with DataCite for some chemical computational modelling files as published in three different repositories. Here I take it one stage further, by looking at how searches of the DataCite metadata store for three particular values of the metadata associated with this dataset compare.

The number of repositories which accept research data across a wide spectrum of disciplines is on the up. Here I report the results of conducting an experiment in which chemical modelling data was deposited in six such repositories and comparing the richness of the metadata describing the essential properties of the six depositions. The repositories are as follows: Figshare as a repository dates from 2012.

You might have noticed if you have read any of my posts here is that many of them have been accompanied since 2006 by supporting calculations, normally based on density functional theory (DFT) and these calculations are accompanied by a persistent identifier pointer ^‡ to a data repository publication.

An earlier post investigated large anomeric effects involving two oxygen atoms attached to a common carbon atom. A variation is to replace one oxygen by a nitrogen atom, as in N-C-O. Shown below is a scatter plot of the two distances to the common carbon atom derived from crystal structures. You can see some entries for which the C-O bond length is shorter than normal and the C-N distance very much longer than normal;