@article{KwesigaKellingKerstingetal.2020,
  author    = {Kwesiga, George and Kelling, Alexandra and Kersting, Sebastian and Sperlich, Eric and von Nickisch-Rosenegk, Markus and Schmidt, Bernd},
  title     = {Total syntheses of prenylated isoflavones from Erythrina sacleuxii and their antibacterial activity},
  series = {Journal of natural products},
  volume    = {83},
  journal   = {Journal of natural products},
  number    = {11},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0163-3864},
  doi       = {10.1021/acs.jnatprod.0c00932},
  pages     = {3445 -- 3453},
  year      = {2020},
  abstract  = {The prenylated isoflavones 5-deoxyprenylbiochanin A (7-hydroxy-4'-methoxy-3'-prenylisoflavone) and erysubin F (7,4'-dihydroxy-8,3'-diprenylisoflavone) were synthesized for the first time, starting from mono-or di-O-allylated chalcones, and the structure of 5-deoxy-3'-prenylbiochanin A was corroborated by single-crystal X-ray diffraction analysis. Flavanones are key intermediates in the synthesis. Their reaction with hypervalent iodine reagents affords isoflavones via a 2,3-oxidative rearrangement and the corresponding flavone isomers via 2,3-dehydrogenation. This enabled a synthesis of 7,4'-dihydroxy-8,3'-diprenylflavone, a non-natural regioisomer of erysubin F. Erysubin F (8), 7,4'-dihydroxy-8,3'-diprenylflavone (27), and 5-deoxy-3'prenylbiochanin A (7) were tested against three bacterial strains and one fungal pathogen. All three compounds are inactive against Salmonella enterica subsp. enterica (NCTC 13349), Escherichia coli (ATCC 25922), and Candida albicans (ATCC 90028), with MIC values greater than 80.0 mu M. The diprenylated natural product erysubin F (8) and its flavone isomer 7,4'-dihydroxy-8,3'diprenylflavone (27) show in vitro activity against methicillin-resistant Staphylococcus aureus (MRSA, ATCC 43300) at MIC values of 15.4 and 20.5 mu M, respectively. In contrast, the monoprenylated 5-deoxy-3'-prenylbiochanin A (7) is inactive against this MRSA strain.},
  language  = {en}
}
@article{KwesigaSperlichSchmidt2021,
  author    = {Kwesiga, George and Sperlich, Eric and Schmidt, Bernd},
  title     = {Scope and applications of 2,3-oxidative aryl rearrangements for the synthesis of isoflavone natural products},
  series = {The journal of organic chemistry},
  volume    = {86},
  journal   = {The journal of organic chemistry},
  number    = {15},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {0022-3263},
  doi       = {10.1021/acs.joc.1c01375},
  pages     = {10699 -- 10712},
  year      = {2021},
  abstract  = {The reaction of flavanones with hypervalent iodine reagents was investigated with a view to the synthesis of naturally occurring isoflavones. In contrast to several previous reports in the literature, we did not observe the formation of any benzofurans via a ring contraction pathway, but could isolate only isoflavones, resulting from an oxidative 2,3-aryl rearrangement, and flavones, resulting from an oxidation of the flavanones. Although the 2,3-oxidative rearrangement allows a synthetically useful approach toward some isoflavone natural products due to the convenient accessibility of the required starting materials, the overall synthetic utility and generality of the reaction appear to be more limited than previous literature reports suggest.},
  language  = {en}
}
@article{SperlichKellingKwesigaetal.2022,
  author    = {Sperlich, Eric and Kelling, Alexandra and Kwesiga, George and Schmidt, Bernd},
  title     = {Intermolecular interactions in the solid-state structures of isoflavones},
  series = {CrystEngComm / The Royal Society of Chemistry},
  volume    = {24},
  journal   = {CrystEngComm / The Royal Society of Chemistry},
  number    = {26},
  publisher = {Royal Society of Chemistry},
  address   = {London},
  issn      = {1466-8033},
  doi       = {10.1039/d2ce00169a},
  pages     = {4731 -- 4739},
  year      = {2022},
  abstract  = {The molecular structures of three closely related isoflavones have been determined by single crystal X-ray diffraction and have been analysed by geometry matching with the CSD, Hirshfeld surface analysis and analysis of stacking interactions with the Aromatic Analyser program (CSD). The formation of the supramolecular structure by non-covalent interactions was studied and substantial differences in the macroscopic properties e.g., the solubility, were correlated with hydrogen bonding and pi-stacking interactions. Moreover, a correlation between the supramolecular structure, the torsion angle (between benzopyran group and aryl group), and macroscopic properties was determined in the three compounds.},
  language  = {en}
}