The nuclei of ordinary hydrogen atoms contain only a single proton. If a neutron is added, the hydrogen becomes deuterium. In principle, molecules that contain deuterium in place of hydrogen atoms are chemically identical. However, there can be significant differences.
Thus “heavy water”, water with molecules that contain deuterium in place of hydrogen, is toxic because it disrupts highly sensitive biochemical processes in the body and leads to metabolic failure. As researchers report in the journal Angewandte Chemie, when the hydrogen atoms of pyridine are replaced with deuterium, it adopts a crystalline form that can only be achieved under high pressure with “normal” pyridine. Perhaps the minimal differences responsible for this type of effect can be implemented to improve the spectrum of properties available to pharmaceutical agents.
Pyridine is a six-membered ring with five carbon atoms and one nitrogen atom. The carbon atoms are each attached to one hydrogen atom. These can be replaced with deuterium. Researchers led by Roland Boese at the University of Duisburg–Essen have discovered that deuterated pyridine crystallizes at about –85 °C with a different crystal structure than that usually adopted by pyridine. In parallel, British researchers working with Simon Parsons determined that non-deuterated pyridine also adopts this structure under high pressure, because it occupies a smaller volume than pyridine’s usual structure.
The replacement of hydrogen by deuterium clearly changes the strength of interactions between individual groups of atoms in neighboring molecules, making other arrangements more energetically favorable. Such interactions between groups of atoms also play an important role in pharmaceuticals, such as when a drug is meant to fit into the binding cavity of an enzyme. Subtle changes can result in significant changes in a drug’s activity. This is why Boese and his team are interested in deuterated pyridine: pyridine is an important starting material for pharmaceuticals, and its basic framework is found in many medications. Boese thinks it likely that deuteration will allow for the development of drug variants that are more specific or have fewer side effects than their conventional precursors.
Author: Roland Boese, Universität Duisburg-Essen (Germany), http://www.structchem.uni-duisburg-essen.de/Dateien/Mitarbeiter/Boese/FR_Boese_en.htm
Title: Isotopic Polymorphism in Pyridine
Angewandte Chemie International Edition 2009, 48, No. 4, 755–757, doi: 10.1002/anie.200803589
Roland Boese | Angewandte Chemie
Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt
Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).
Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...
Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.
The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...
UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration
"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...
Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.
Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...
10.01.2017 | Event News
09.01.2017 | Event News
05.01.2017 | Event News
16.01.2017 | Power and Electrical Engineering
16.01.2017 | Information Technology
16.01.2017 | Power and Electrical Engineering