RESUMO
Invited for the cover of this issue are Valery Andrushchenko, Monika Krupová, and co-workers at the Institute of Organic Chemistry and Biochemistry (IOCB Prague) of the Czech Academy of Sciences. The image depicts a "crystal city" illuminated by "chiral suns" shining left- and right-circularly polarized light (L-CPL and R-CPL), which reveals differences in the structure of the chiral crystalline "skyscrapers". Designed by Tomás Bellon @ IOCB Prague. Read the full text of the article at 10.1002/chem.202201922.
Assuntos
Dicroísmo Circular , Nucleosídeos , Nucleosídeos/químicaRESUMO
Vibrational circular dichroism (VCD) spectroscopy has been widely used to study (bio)molecules in solution. However, its solid-state applications have been restricted due to experimental limitations and artifacts. Having overcome some of them, the first VCD study of nucleoside crystals is now presented. A two-orders-of-magnitude enhancement of VCD signal was observed due to high molecular order in the crystals and resulting supramolecular chirality. This allowed to obtain high-quality VCD spectra within minutes using minute amounts of samples. The VCD technique is extremely sensitive in detecting changes in a crystal order and is able to distinguish different hydration states of crystals. This elevates it to a new level, as a fast and efficient tool to study chiral crystalline samples. This study demonstrates that VCD is capable of near-instantaneous detection of hydration polymorphs and crystal degradation, which is of substantial interest in pharmaceutical industry (quality and stability control).
