A5025793097- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Crystallography and molecular interactions
- Organoboron and organosilicon chemistry
- Steroid Chemistry and Biochemistry
- Estrogen and related hormone effects
- Chemical Synthesis and Analysis
- Synthesis and characterization of novel inorganic/organometallic compounds
- Advanced Chemical Physics Studies
- Catalytic Cross-Coupling Reactions
- Machine Learning in Materials Science
- Coordination Chemistry and Organometallics
- Nitric Oxide and Endothelin Effects
- Synthesis and pharmacology of benzodiazepine derivatives
- Synthetic Organic Chemistry Methods
- Renin-Angiotensin System Studies
- Hormonal Regulation and Hypertension
- Various Chemistry Research Topics
- Receptor Mechanisms and Signaling
- Chemical Thermodynamics and Molecular Structure
- Molecular spectroscopy and chirality
- Advanced NMR Techniques and Applications
- Oxidative Organic Chemistry Reactions
- Carbohydrate Chemistry and Synthesis
- Chemical Synthesis and Reactions
University of Bonn
2021-2025
Fraunhofer Institute for Chemical Technology
2023
University of Würzburg
2018-2020
Medical University of Vienna
2020
Institute of Inorganic Chemistry of the Slovak Academy of Sciences
2019
Roche (Switzerland)
1963-2001
University of Wisconsin–Madison
2000
Novartis (Switzerland)
1996
Federal Government of Germany
1977
La Roche College
1963-1973
Conformer–rotamer sampling tool (CREST) is an open-source program for the efficient and automated exploration of molecular chemical space. Originally developed in Pracht et al. [Phys. Chem. Phys. 22, 7169 (2020)] as driver calculations at extended tight-binding level (xTB), it offers a variety molecular- metadynamics simulations, geometry optimization, structure analysis capabilities. Implemented algorithms include procedures conformational sampling, explicit solvation studies, calculation...
A new composite density functional theory (DFT) method is presented. It based on ωB97X-V as one of the best-performing functionals for GMTKN55 thermochemistry database and completes family "3c" methods toward range-separated hybrid DFT. This consistently available all elements up to Rn (Z = 1-86). Its further key ingredients are a polarized valence double-ζ (vDZP) Gaussian basis set, which was fully optimized in molecular DFT calculations, combination with large-core effective core...
Many low-cost or semiempirical quantum mechanical-based electronic structure methods suffer from the use of unpolarized minimal atomic orbital (AO) basis sets. In this work, we overcome limitation by a fully DFT variationally optimized, adaptive set consistently available for elements up to radon (Z = 86). The new key feature is make linear coefficients primitive Gaussians in contracted AO dependent on effective charge atom molecule, i.e., each symmetry-unique obtains its "own" specifically...
The potent and selective GP IIb-IIIa antagonist lamifiban (1, Ro 44-9883) is currently in clinical development as an injectable antithrombotic agent for treating preventing acute coronary syndromes. However, secondary prevention of thrombotic occlusions, orally active inhibitors are needed. By means a prodrug strategy, the modest oral absorption 1 mice was improved by factor 9. In addition, these studies demonstrated that amidoxime group can serve functionality amidino group. Application...
Existing semiempirical molecular orbital methods suffer from the usually minimal atomic-orbital (AO) basis set used to simplify calculations. Here, a completely new and consistently parameterized tight-binding electronic structure Hamiltonian evaluated in deeply contracted, properly polarized valence double-zeta (vDZP) is described. The inner-shell electrons are accounted for by standard, large-core effective potentials approximations them. primary target of this so-called density matrix...
The accurate and efficient assignment of atomic partial charges is crucial for many applications in theoretical computational chemistry, including polarizable force fields, dispersion corrections, charge-dependent basis sets. Classical charge models struggle to distinguish between neutral zwitterionic fragments because, unlike quantum mechanical methods, there are no discrete electronic states. This limitation can lead either reduced or additional artificial transfer (CT) at different...
A new pathway for the ring expansion reaction of antiaromatic boroles with organic azides is reported. While usually leads to 1,2-azaborinines, it was diverted formation a 1,2,3-diazaborinine by changing electronic characteristics reagents. The isolable azo-azaborinine intermediate initially formed from 1-(2,3,4,5-tetraphenylborolyl)ferrocene 4-azido-N,N-dimethylaniline gradually decomposed and benzonitrile. Both spectroscopic properties reactivity heteroaromatic compound show analogies...
The reactions of organic azides with diaryl(dihalo)diboranes(4) were explored, resulting in the observation a number surprising reactivity patterns. reaction phenyl azide 1,2-diaryl-1,2-dihalodiboranes(4) resulted formation five-membered rings comprising diboryl-triazenes retention boron-boron bond, while peculiar 1,1-di(9-anthryl)-2,2-difluorodiborane(4) yielded six-membered ring bearing diboryl-triazene, whereby B-B bond was ruptured by insertion an arylnitrene-like reactive intermediate....
Phenylamino-pyrimidines represent a novel class of inhibitors the protein kinase C with high degree selectivity versus other serine/threonine and tyrosine kinases. Steady state kinetic analysis N-(3-[1-imidazolyl]-phenyl-4-(3-pyridyl)-2-pyrimidinamine (5), which showed potent inhibitory activity, revealed competitive kinetics relative to ATP. The adjacent H-bond acceptor pyrimidine moiety next an donor phenylamine was found be crucial for activity....
Crystallization-induced asymmetric transformation (AT) has been achieved with the salicaldimine complexes 8/9, 11/12, and 14a/15a oxazaborolidinone 22b/23b 22c/23c. In case of 22a 23a, initially formed 3:1 mixture diastereomers crystallizes under equilibrium conditions to afford a quasi-racemate 24, containing both in unit cell. Enolate formation from ent-22b is demonstrated, methylation occurs give 26a. Aldol condensation enolate also feasible, hindered aldehydes adducts such as 27a or 27b...
Abstract Es wird die Synthese des 18‐Nor‐progesterons und analoger 18‐Nor‐Derivate beschrieben.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSyntheses of 14,15,16,17-Tetrahydroerythrinane1,2V. Boekelheide, Marcel Müller, J. Jack, T. Grossnickle, and M. ChangCite this: Am. Chem. Soc. 1959, 81, 15, 3955–3959Publication Date (Print):August 1, 1959Publication History Published online1 May 2002Published inissue 1 August 1959https://pubs.acs.org/doi/10.1021/ja01524a035https://doi.org/10.1021/ja01524a035research-articleACS PublicationsRequest reuse permissionsArticle...
The γ-nitrogen insertion of arylazides into the B-B bond electron-rich cyclic μ-hydridodiboranes stabilised by one N-heterocyclic carbene (NHC) ligand leads to expansion central C3B2 ring, yielding unsymmetrical polyheterocyclic 1,1-diboryltriazenes. 2-benzyl-bridged analogues undergo further NHC ring and thermally induced loss N2.
Abstract Es werden weitere Steroid‐Derivate beschrieben, in welchen der Ring D des Gerüstes unter Einführung einer Methylen‐Gruppierung an C‐13 geöffnet ist. Diese neue Klasse von Verbindungen soll als Ausgangsmaterial für Versuche zur Sauerstoff‐funktion das anguläre Methyl dienen.
A set of diboryldiborenes are prepared by the mild, catalyst-free, room-temperature diboration B-B triple bonds doubly base-stabilized diborynes. Two product found to be air- and water-stable in solid state, an effect that is attributed their high crystallinity extreme insolubility a wide range solvents.
The addition of alkynes to a saturated N-heterocyclic carbene (NHC)-supported diboryne results in spontaneous cycloaddition, with complete B[triple bond, length as m-dash]B and C[triple m-dash]C triple bond cleavage, NHC ring-expansion activation variety C-H bonds, leading the formation complex mixtures fused B,N-heterocycles.