A5004010318- Mass Spectrometry Techniques and Applications
- Analytical chemistry methods development
- Analytical Chemistry and Chromatography
- Ion-surface interactions and analysis
- Isotope Analysis in Ecology
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Entomological Studies and Ecology
- Forest Insect Ecology and Management
- Advanced Proteomics Techniques and Applications
- Metabolomics and Mass Spectrometry Studies
- Supramolecular Chemistry and Complexes
- Crystallography and molecular interactions
- Ionic liquids properties and applications
- Chemical Synthesis and Analysis
- Electrohydrodynamics and Fluid Dynamics
- Fullerene Chemistry and Applications
- Erythrocyte Function and Pathophysiology
- Environmental Science and Technology
- Catalytic C–H Functionalization Methods
- Molecular Sensors and Ion Detection
- Plant Physiology and Cultivation Studies
- Advanced Chemical Physics Studies
- Spectroscopy Techniques in Biomedical and Chemical Research
- Synthesis and Properties of Aromatic Compounds
Heidelberg University
2015-2024
Darmstadt University of Applied Sciences
1991-2013
Heidelberg University
2004-2008
University of Würzburg
1968
University of Pittsburgh
1959
Carnegie Institution for Science
1959
Chiral self-sorting is intricately connected to the complicated chiral processes observed in nature and no artificial systems of comparably complexity have been generated by chemists. However, only a few examples purely organic molecules reported so far, where process could be controlled. Herein, we describe large cubic [8+12] salicylimine cage compounds based on TBTQ precursor. Out 23 possible isomers enantiopure meso were formed, which unambiguously characterized single crystal X-ray...
Abstract Mechanically interlocked structures, such as catenanes and rotaxanes, are fascinating synthetic targets some used for molecular switches machines. Today, the vast majority of catenated structures built upon macrocycles only a very few examples three-dimensional shape-persistent organic cages forming have been reported. However, catenation in all these cases was based on thermodynamically favoured π – π- stacking under certain reaction conditions. Here, we show that catenane...
Mechanically interlocked structures are fascinating synthetic targets and the topological complexity achieved through catenation offers numerous possibilities for construction of new molecules with exciting properties. In structural space catenated organic cage molecules, only few examples have been realized so far, control over process in solution is still barely achieved. Herein, we describe formation a quadruply catenane giant chiral [8+12] salicylimine cubes. The could be controlled by...
Atmospheric pressure field desorption (APFD) mass spectrometry (MS) has recently been introduced as a new variant of (FD) spectrometry. The development aimed at providing the basic characteristics FD-MS in combination with instruments equipped an atmospheric (AP) interface. Hitherto, APFD demonstrated to yield both positive and negative even electron ions highly polar or ionic compounds well enable generation molecular ions, M
A gold(I)-catalyzed cascade cyclization-alkynylation of allenoates using alkynyl bromide to generate β-alkynyl-γ-butenolides was investigated. Whereas iodides afforded significant amounts the homo-coupling two lactone units, bromides led a selective reaction, and broad functional group tolerance observed. Under optimized reaction conditions, it possible directly synthesize large range in moderate good yields without need for any external oxidant.
The BGOOD photoproduction experiment accesses forward meson angles and low momentum exchange kinematics in the $uds$ sector, which may be sensitive to molecular-like hadron structure. Our results strangeness sector suggest a dominant role of meson-baryon dynamics. This includes structures $K^0\Sigma^0$, $K^+\Sigma^0$ $K^+\Sigma^0(1385)$ residing at $\Sigma^{(*)}K^{(*)}$ thresholds have an equivalence $P_C$ states $\Sigma_C^{(*)}\bar D^{(*)}$ thresholds. In non-strange baryon-baryon...
Biochemical and clinical evidence indicates that monomethylated selenium compounds are crucial for the tumor preventive effects of trace element methylselenol (CH<sub>3</sub>SeH) is a key metabolite. As suggested by Ganther (Ganther, H. E. (1999)<i>Carcinogenesis</i> 20, 1657–1666), its precursor methylseleninate might exert their inhibition selenoenzyme thioredoxin reductase via irreversible formation diselenide bridge. Here we report does not act as an inhibitor mammalian but in fact...
A new type of mediator for cobalt(II)-mediated radical polymerization is reported which based on 1,3-bis(2-pyridylimino)isoindolate (bpi) as ancillary ligand. The modular synthesis the bis(pyridylimino)isoindoles (bpiH) employed in this work condensation 2-aminopyridines with phthalodinitriles. Reaction bpiH protio-ligands a twofold excess cobalt(II) acetate or acetylacetonate methanol gave [Co(bpi)(OAc)], crystallize coordination polymers, and series [Co(acac)(bpi)(MeOH)], are mononuclear...
Abstract Diazabicyclo[2.2.2]octane (DABCO) has been used as a mild and efficient catalyst for synthesis of 2‐amino‐3‐cyano naphthopyran derivatives via one‐pot three‐component reaction aromatic aldehydes, naphthols, malononitrile at room temperature. The short times, easy workup, good to excellent yields, conditions make this domino Knoevenagel–Michael both practical attractive.
Ionic liquids form neutral ion pairs (CA) upon evaporation. The softness of the gas-phase ionization field has been used to generate "molecular ions," CA(+*), ionic liquids, most probably by neutralization anion. In detail, 1-ethyl-3-methylimidazolium-thiocyanate, [C(6)H(11)N(2)](+) [SCN](-), 1-butyl-3-methylimidazolium-tricyanomethide, [C(8)H(15)N(2)](+) [C(4)N(3)](-), N-butyl-3-methylpyridinium-dicyanamide, [C(10)H(16)N](+) [C(2)N(3)](-), and...
Abstract Chiral self‐sorting is intricately connected to the complicated chiral processes observed in nature and no artificial systems of comparably complexity have been generated by chemists. However, only a few examples purely organic molecules reported so far, where process could be controlled. Herein, we describe large cubic [8+12] salicylimine cage compounds based on TBTQ precursor. Out 23 possible isomers enantiopure meso were formed, which unambiguously characterized single crystal...
How does the catalytic set-up of a hydrolase activate H2O2 for enzymatic oxidations? The oxidizing species is peracid, as these studies with metal-free haloperoxidases CPO-P and CPO-T clearly show. analogy between haloperoxidase reactions elucidated in below.
The areoles and spines of cacti can be used to desorb ions ionic liquids (ILs) by the mere action an electric field into atmospheric pressure (AP) interface a mass spectrometer. small cactus species Opuntia microdasys bears numerous very fine hairs on its tiny sharp that appeared suited serve as needle electrodes enough for desorption occur. In fact, positive negative four ILs could desorbed process analogous AP (APFD). contrast APFD where activated emitters are employed, were deposited onto...
Direct analysis in real time-mass spectrometry (DART-MS) enables screening of articles daily use made polydimethylsiloxanes (PDMS), commonly known as silicone rubber, to assess their tendency release low molecular weight oligomers. DART-MS analyses were performed on a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Flexible baking molds, watch band, and dough scraper, baby different brands pacifiers, nipples, teething ring have been examined. While somewhat arbitrarily...