@article{SchildeKellingUmbreenetal.2016,
  author    = {Schilde, Uwe and Kelling, Alexandra and Umbreen, Sumaira and Linker, Torsten},
  title     = {Crystal structures of three bicyclic carbohydrate derivatives},
  series = {Acta crystallographica, Section E, Crystallographic communications},
  volume    = {72},
  journal   = {Acta crystallographica, Section E, Crystallographic communications},
  publisher = {International Union of Crystallography},
  address   = {Chester},
  issn      = {2056-9890},
  doi       = {10.1107/S2056989016018727},
  pages     = {1839 -- +},
  year      = {2016},
  abstract  = {The title compounds, [(1R,3R,4R,5R,6S)-4,5-bis(acetyloxy)-7-oxo-2-oxabicyclo-[4.2.0]octan-3-yl]methyl acetate, C14H18O8, (I), [(1S,4R,5S,6R)-5-acetyloxy-7-hydroxyimino-2-oxobicyclo[4.2.0] octan-4-yl acetate, C11H15NO6, (II), and [(3aR, 5R, 6R, 7R, 7aS)-6,7-bis(acetyloxy)-2-oxooctahydropyrano[3,2-b]pyrrol-5-yl] methyl acetate, C14H19NO8, (III), are stable bicyclic carbohydrate derivatives. They can easily be synthesized in a few steps from commercially available glycals. As a result of the ring strain from the four-membered rings in (I) and (II), the conformations of the carbohydrates deviate strongly from the ideal chair form. Compound (II) occurs in the boat form. In the five-membered lactam (III), on the other hand, the carbohydrate adopts an almost ideal chair conformation. As a result of the distortion of the sugar rings, the configurations of the three bicyclic carbohydrate derivatives could not be determined from their NMR coupling constants. From our three crystal structure determinations, we were able to establish for the first time the absolute configurations of all new stereocenters of the carbohydrate rings.},
  language  = {en}
}
@article{SchildePazOrtiz2017,
  author    = {Schilde, Uwe and Paz, Christian and Ortiz, Leandro},
  title     = {Crystal structure of erioflorin isolated from Podanthus mitiqui (L.)},
  series = {Acta Crystallographica Section E : Crystallographic Communications},
  volume    = {73},
  journal   = {Acta Crystallographica Section E : Crystallographic Communications},
  number    = {3},
  publisher = {International Union of Crystallography},
  address   = {Chester},
  doi       = {10.1107/S2056989017001700},
  pages     = {334 -- 337},
  year      = {2017},
  abstract  = {The title compound, erioflorin, C19H24O6 [systematic name: (1aR,3S,4Z,5aR,8aR,9R,10aR)-1a, 2,3,5a, 7,8,8a, 9,10,10a-decahydro-3-hydroxy-4,10a-dimethyl-8-methylidene-7-oxooxireno[5,6] cyclodeca[1,2-b]furan-9-yl methacrylate], is a tricyclic germacrane sesquiterpene lactone, which was isolated from Podanthus mitiqui (L.). The compound crystallizes in the space group P2(1)2(1)2(1), and its molecular structure consists of a methacrylic ester of a ten-membered ring sesquiterpenoid annelated with an epoxide and a butyrolactone. The structure is stabilized by one intramolecular C-H center dot center dot center dot O hydrogen bond. An O-H center dot center dot center dot O hydrogen bond and further C-H center dot center dot center dot O interactions can be observed in the packing.},
  language  = {en}
}
@article{SchildeKellingUmbreenetal.2016,
  author    = {Schilde, Uwe and Kelling, Alexandra and Umbreen, Sumaira and Linker, Torsten},
  title     = {Crystal structures of three bicyclic carbohydrate derivatives},
  series = {Acta crystallographica Section E ; Crystallographic communications},
  volume    = {72},
  journal   = {Acta crystallographica Section E ; Crystallographic communications},
  number    = {12},
  publisher = {IUCR},
  address   = {Chester},
  issn      = {2056-9890},
  doi       = {10.1107/S2056989016018727},
  pages     = {1839 -- 1844},
  year      = {2016},
  abstract  = {The title compounds, [(1R,3R,4R,5R,6S)-4,5-bis(acetyloxy)-7-oxo-2-oxabicyclo- [4.2.0]octan-3-yl]methyl acetate, C14H18O8, (I), [(1S,4R,5S,6R)-5-acetyloxy-7- hydroxyimino-2-oxobicyclo[4.2.0]octan-4-yl acetate, C11H15NO6, (II), and [(3aR,5R,6R,7R,7aS)-6,7-bis(acetyloxy)-2-oxooctahydropyrano[3,2-b]pyrrol-5- yl]methyl acetate, C14H19NO8, (III), are stable bicyclic carbohydrate derivatives. They can easily be synthesized in a few steps from commercially available glycals. As a result of the ring strain from the four-membered rings in (I) and (II), the conformations of the carbohydrates deviate strongly from the ideal chair form. Compound (II) occurs in the boat form. In the five-membered lactam (III), on the other hand, the carbohydrate adopts an almost ideal chair conformation. As a result of the distortion of the sugar rings, the configurations of the three bicyclic carbohydrate derivatives could not be determined from their NMR coupling constants. From our three crystal structure determinations, we were able to establish for the first time the absolute configurations of all new stereocenters of the carbohydrate rings.},
  language  = {en}
}