@article{ZborowskiKochKleinpeteretal.2014,
  author    = {Zborowski, Krzysztof Kazimierz and Koch, Andreas and Kleinpeter, Erich and Proniewicz, Leonard Marian},
  title     = {Searching for aromatic celate rings. Oxygen versus Thio and Seleno Ligands},
  series = {Zeitschrift f{\"u}r physikalische Chemie : international journal of research in physical chemistry and chemical physics},
  volume    = {228},
  journal   = {Zeitschrift f{\"u}r physikalische Chemie : international journal of research in physical chemistry and chemical physics},
  number    = {8},
  publisher = {De Gruyter},
  address   = {Berlin},
  issn      = {0942-9352},
  doi       = {10.1515/zpch-2014-0528},
  pages     = {869 -- 878},
  year      = {2014},
  abstract  = {As a part of searching for fully aromatic chelate compounds, copper complexes of malondialdehyde as well as its sulfur and selenium derivatives were investigated using the DFT quantum chemical methods. Chelate complexes of both Cu(I) and Cu(II) ions wereconsidered. Aromaticity of the metal complexes studied were analyzed using NICS(0), NICS(1), PDI, I-ring, MCI, ICMCI and I-B aromaticity indices, and by TSNMRS visualizations of the spatial magnetic properties. It seems that partial aromaticityof studied chelates increases when oxygen atoms in malondialdehyde are replaced by sulfur and selenium.},
  language  = {en}
}
@article{MuivaMutisyaMachariaHeydenreichetal.2014,
  author    = {Muiva-Mutisya, Lois and Macharia, Bernard and Heydenreich, Matthias and Koch, Andreas and Akala, Hoseah M. and Derese, Solomon and Omosa, Leonidah K. and Yusuf, Amir O. and Kamau, Edwin and Yenesew, Abiy},
  title     = {6 alpha-Hydroxy-alpha-toxicarol and (+)-tephrodin with antiplasmodial activities from Tephrosia species},
  series = {Phytochemistry letters},
  volume    = {10},
  journal   = {Phytochemistry letters},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {1874-3900},
  doi       = {10.1016/j.phytol.2014.09.002},
  pages     = {179 -- 183},
  year      = {2014},
  abstract  = {The CH2Cl2/MeOH (1: 1) extract of the roots of Tephrosia villosa showed good antiplasmodial activity against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum with IC50 values of 3.1 +/- 0.4 and 1.3 +/- 0.3 mu g/mL, respectively. Chromatographic separation of the extract yielded a new rotenoid, 6 alpha-hydroxy-alpha-toxicarol, along with five known rotenoids, (rotenone, deguelin, sumatrol, 12 alpha-hydroxy-alpha-toxicarol and villosinol). Similar treatment of the extract of the stem of Tephrosia purpurea (IC50 = 4.1 +/- 0.4 and 1.9 +/- 0.2 mu g/mL against D6 and W2 strains of P. falciparum, respectively) yielded a new flavone having a unique substituent at C-7/C-8 [trivial name (+)-tephrodin], along with the known flavonoids tachrosin, obovatin methyl ether and derrone. The relative configuration and the most stable conformation in (+)-tephrodin was determined by NMR and theoretical energy calculations. The rotenoids and flavones tested showed good to moderate antiplasmodial activities (IC50 = 9 +/- 23 mu M). Whereas the cytotoxicity of rotenoids is known, the flavones (+)-tephrodin and tachrosin did not show significant cytotoxicity (IC50 > 100 mu M;) against mammalian African monkey kidney (vero) and human larynx carcinoma (HEp2) cell lines. (C) 2014 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved.},
  language  = {en}
}
@article{KleinpeterKochSchulzetal.2014,
  author    = {Kleinpeter, Erich and Koch, Andreas and Schulz, Stefanie and Wacker, Philipp},
  title     = {Interplay of para- and diatropic ring currents [(anti)aromaticity] of macrocyclic rings subject to conformational influences, further annelation and hydrogenation of aromatic ring moieties},
  series = {Tetrahedron},
  volume    = {70},
  journal   = {Tetrahedron},
  number    = {48},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0040-4020},
  doi       = {10.1016/j.tet.2014.10.018},
  pages     = {9230 -- 9239},
  year      = {2014},
  abstract  = {The spatial magnetic properties (Through Space NMR Shieldings-TSNMRS) of a variety of porphyrins, hemiporphyrazines and tetraoxo[8]circulenes have been computed, visualized as Iso-chemical Shielding Surfaces (ICSS) of various size and direction, and were examined subject to the interplay of present (para)-diatropic ring currents [(anti)aromaticity] and influences on the latter property originating from the macrocyclic ring conformation, further annelation and partial to complete hydrogenation of aromatic ring moieties. Caution seems to be indicated when concluding from a single NICS parameter to present (para)diatropic ring currents [(anti)aromaticity]. (C) 2014 Elsevier Ltd. All rights reserved.},
  language  = {en}
}