@article{BelasriTopalHeydenreichetal.2020,
  author    = {Belasri, Khadija and Topal, Leila and Heydenreich, Matthias and Koch, Andreas and Kleinpeter, Erich and Fulop, Ferenc and Szatmari, Istvan},
  title     = {Synthesis and conformational analysis of naphthoxazine-fused phenanthrene derivatives},
  series = {Molecules},
  volume    = {25},
  journal   = {Molecules},
  number    = {11},
  publisher = {MDPI},
  address   = {Basel},
  issn      = {1420-3049},
  doi       = {10.3390/molecules25112524},
  pages     = {15},
  year      = {2020},
  abstract  = {The synthesis of new phenanthr[9,10-e][1,3]oxazines was achieved by the direct coupling of 9-phenanthrol with cyclic imines in the modified aza-Friedel-Crafts reaction followed by the ring closure of the resulting bifunctional aminophenanthrols with formaldehyde. Aminophenanthrol-type Mannich bases were synthesised and transformed to phenanthr[9,10-e][1,3]oxazines via [4 + 2] cycloaddition. Detailed NMR structural analyses of the new polyheterocycles as well as conformational studies including Density Functional Theory (DFT) modelling were performed. The relative stability of ortho-quinone methides (o-QMs) was calculated, the geometries obtained were compared with the experimentally determined NMR structures, and thereby, the regioselectivity of the reactions has been assigned.},
  language  = {en}
}
@article{ShainyanMoskalikHeydenreichetal.2014,
  author    = {Shainyan, Bagrat A. and Moskalik, Mikhail Yu and Heydenreich, Matthias and Kleinpeter, Erich},
  title     = {Conformational equilibrium and dynamic behavior of bis-N-triflyl substituted 3,8-diazabicyclo[3.2.1]octane},
  series = {Magnetic resonance in chemistry},
  volume    = {52},
  journal   = {Magnetic resonance in chemistry},
  number    = {8},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0749-1581},
  doi       = {10.1002/mrc.4086},
  pages     = {448 -- 452},
  year      = {2014},
  abstract  = {Restricted rotation about the N-S partial double bonds in a bis-N-triflyl substituted 3,8-diazabicyclo[3.2.1]octane derivative 1 has been frozen at low temperature (Delta G* = 11.6 kcal mol(-1)), and the existence of all four rotamers about the two N-S bonds, 3-in, 8-in, 3-in, 8-out, 3-out, 8-in, and 3-out, 8-out, respectively, proved experimentally by NMR spectroscopy and theoretically by DFT and MP2 calculations. Copyright (C) 2014 John Wiley \& Sons, Ltd.},
  language  = {en}
}
@article{KleinpeterLaemmermannKuehn2011,
  author    = {Kleinpeter, Erich and Laemmermann, Anica and K{\"u}hn, Heiner},
  title     = {Synthesis and NMR spectra of the syn and anti isomers of substituted cyclobutanes-evidence for steric and spatial hyperconjugative interactions},
  series = {Tetrahedron},
  volume    = {67},
  journal   = {Tetrahedron},
  number    = {14},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0040-4020},
  doi       = {10.1016/j.tet.2011.02.012},
  pages     = {2596 -- 2604},
  year      = {2011},
  abstract  = {The syn and anti isomers of cis,cis-tricyclo[5.3.0.0(2.6)]dec-3-ene derivatives have been synthesized and their (1)H and (13)C NMR spectra unequivocally analyzed. Both their structures and their (1)H and (13)C NMR chemical shifts were calculated by DFT, the latter two calculations employing the GIAO perturbation method. Additionally, calculated NMR shielding values were partitioned into Lewis and non-Lewis contributions from the bonds and lone pairs involved in the molecules by accompanying NBO and NCS analyses. The differences between the syn and anti isomers were evaluated with respect to steric and spatial hyperconjugation interactions.},
  language  = {en}
}
@article{PihlajaSinkkonenStajeretal.2011,
  author    = {Pihlaja, Kalevi and Sinkkonen, Jari and Stajer, Geza and Koch, Andreas and Kleinpeter, Erich},
  title     = {1-Oxo-1,3-dithiolanes - synthesis and stereochemistry},
  series = {Magnetic resonance in chemistry},
  volume    = {49},
  journal   = {Magnetic resonance in chemistry},
  number    = {7},
  publisher = {Wiley-Blackwell},
  address   = {Malden},
  issn      = {0749-1581},
  doi       = {10.1002/mrc.2764},
  pages     = {443 -- 449},
  year      = {2011},
  abstract  = {1-Oxo-1,3-dithiolane (4) and its cis- and trans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO(4) in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with (1)H and (13)C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=O(ax) envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=O(ax) (30 and 27\%) as well as S=O(eq) (21 and 22\%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of (1)H-(1)H coupling constants and (1)H and (13)C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data.},
  language  = {en}
}
@article{KramerKleinpeter2011,
  author    = {Kramer, Markus and Kleinpeter, Erich},
  title     = {A conformational study of N-acetyl glucosamine derivatives utilizing residual dipolar couplings},
  series = {Journal of magnetic resonance},
  volume    = {212},
  journal   = {Journal of magnetic resonance},
  number    = {1},
  publisher = {Elsevier},
  address   = {San Diego},
  issn      = {1090-7807},
  doi       = {10.1016/j.jmr.2011.06.029},
  pages     = {174 -- 185},
  year      = {2011},
  abstract  = {The conformational analyses of six non-rigid N-acetyl glucosamine (NAG) derivatives employing residual dipolar couplings (RDCs) and NOEs together with molecular dynamics (MD) simulations are presented. Due to internal dynamics we had to consider different conformer ratios existing in solution. The good quality of the correlation between theoretically and experimentally obtained RDCs show the correctness of the calculated conformers even if the ratios derived from the MD simulations do not exactly meet the experimental data. If possible, the results were compared to former published data and commented.},
  language  = {en}
}
@article{CsuetoertoekiSzatmariKochetal.2011,
  author    = {Csuetoertoeki, Renata and Szatmari, Istvan and Koch, Andreas and Heydenreich, Matthias and Kleinpeter, Erich and Fueloep, Ferenc},
  title     = {Synthesis and conformational analysis of new naphth[1,2-e][1,3]oxazino[3,4-c]quinazoline derivatives},
  series = {Tetrahedron},
  volume    = {67},
  journal   = {Tetrahedron},
  number    = {44},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0040-4020},
  doi       = {10.1016/j.tet.2011.08.074},
  pages     = {8564 -- 8571},
  year      = {2011},
  abstract  = {A new highly functionalized aminonaphthol derivative, 1-(amino(2-aminophenyl)methyl)-2-naphthol (4), was synthesized by the reaction of 2-naphthol, 2-nitrobenzaldehyde and tert-butyl carbamate or benzyl carbamate, followed by reduction and/or removal of the protecting group. The aminonaphthol derivative thus obtained was converted in ring-closure reactions with formaldehyde. benzaldehyde and/or phosgene to the corresponding naphth[1,2-e][1,3]oxazino[3,4-c]quinazoline derivatives. The conformational analysis of some derivatives by NMR spectroscopy and accompanying molecular modelling are also reported.},
  language  = {en}
}