A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution

Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine-intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state-of-the-art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined

A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution

Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine-intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state-of-the-art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined. © 2020 The Authors. Published by Wiley-VCH Gmb

Inhibitors of dihydroorotate dehydrogenase cooperate with molnupiravir and N4-hydroxycytidine to suppress SARS-CoV-2 replication

Funding Information: We thank Thorsten Wolff, Daniel Bourquain, Jessica Schulz, and Christian Mache from the Robert-Koch Institute and Martin Beer from the Friedrich Loeffler Institute (FLI) for providing isolates of SARS-CoV-2 variants. We thank Anna Kraft and Gabriele Czerwinski (both FLI) for support in the preparation of samples for pathology, and Catherine Hambly (University of Aberdeen) for help with daily energy expenditure measurements. We would like to thank Cathrin Bierwirth (University Medical Center Göttingen), Isabell Schulz, Anne-Kathrin Donner, and Frank-Thorben Peters for excellent technician assistance and Jasmin Fertey and Alexandra Rockstroh for providing the virus stocks for the mice experiment (Fraunhofer Institute IZI Leipzig). We acknowledge support by the Open Access Publication Funds of the Göttingen University. KMS was a member of the Göttingen Graduate School GGNB during this work. This work was funded by the COVID-19 Forschungsnetzwerk Niedersachsen (COFONI) to MD, by the Federal Ministry of Education and Research Germany ( Bundesministerium für Bildung und Forschung; BMBF ; OrganSARS , 01KI2058 ) to SP and TM, and by a grant of the Max Planck Foundation to DG. Declaration of interests AS, HK, EP, and DV are employees of Immunic AG and own shares and/or stock-options of the parent company of Immunic AG, Immunic Inc. Some of the Immunic AG employees also hold patents for the Immunic compounds described in this manuscript (WO2012/001,148, WO03006425). KMS, AD, and MD are employees of University Medical Center Göttingen, which has signed a License Agreement with Immunic AG covering the combination of DHODH inhibitors and nucleoside analogs to treat viral infections, including COVID-19 (inventors: MD, KMS, and AD). The other authors declare no conflict of interest.Peer reviewedPublisher PD

Characterization and in ovo vascularization of a 3D-printed hydroxyapatite scaffold with different extracellular matrix coatings under perfusion culture

For the fabrication of appropriate bone tissue-engineered constructs several prerequisites should be fulfilled. They should offer long-term stability, allow proper cell attachment and proliferation and furthermore be osteoinductive and easy to be vascularized. Having these requirements as background, we fabricated a novel porous 3D-printed hydroxyapatite (HA) scaffold and treated it with oxygen plasma (OPT). MG-63 pre-osteoblast-seeded bone constructs allowed good cell attachment and proliferation, which was even better when cultivated in a perfusion flow bioreactor. Moreover, the deposition of extracellular matrix (ECM) on the otherwise inorganic surface changed the mechanical properties in a favourable manner: elasticity increased from 42.95±1.09 to 91.9±5.1 MPa (assessed by nanoindentation). Compared to static conditions, osteogenic differentiation was enhanced in the bioreactor, with upregulation of ALP, collagen I and osteocalcin gene expression. In parallel experiments, primary human bone marrow mesenchymal stromal cells (hBMSCs) were used and findings under dynamic conditions were similar; with a higher commitment towards osteoblasts compared to static conditions. In addition, angiogenic markers CD31, eNOS and VEGF were upregulated, especially when osteogenic medium was used rather than proliferative medium. To compare differently fabricated ECMs in terms of vascularization, decellularized constructs were tested in the chorioallantoic membrane (CAM) assay with subsequent assessment of the functional perfusion capacity by MRI in the living chick embryo. Here, vascularization induced by ECM from osteogenic medium led to a vessel distribution more homogenous throughout the construct, while ECM from proliferative medium enhanced vessel density at the interface and, to a lower extent, at the middle and top. We conclude that dynamic cultivation of a novel porous OPT HA scaffold with hBMSCs in osteogenic medium and subsequent decellularization provides a promising off-the-shelf bone tissue-engineered construct