Schoffers Research Projects
Synthesis of Rhizopines as Mediators for Nitrogen Fixation
1,10-Phenanthroline as a Template for Catalyst and Sensor Design
Additional Research Information
  Brief Descriptions
  1. Synthesis of Rhizopines as Mediators for Nitrogen Fixation:
  Today about 3% of the world's energy is consumed to make artifical fertilizers which are also problematic once they are applied in gardens and on farm fields. In nature, microorganisms are far more effective by converting atmospheric nitrogen into a form that plants can utilize to grow faster and better. This process is called nitrogen fixation and is based on the symbiotic relationship between plants and bacteria in the soil. Yet the mechanism of nitrogen fixation is not well understood. It is necessary to further investigate which factors play a pivotal role. Such knowledge could help reduce adverse effects of conventional fertilizers and better protect the environment. We focus on the synthesis of specific inosamines that have been identified as nutritional mediators in the root area of plants (rhizosphere). The challenging structure of 3-O-methyl-scyllo-inosamine displays dense functionality and stereochemistry. The carbohydrate-like target molecule attracted our’ attention due to the potential involvement in plant signal-transduction and how it can affect crop yield and lower the use of energy-intensive fertilizers for common crop. Because the target is available in only minute amounts in legume plants,we are not only interested in the preparation of larger quantities but also in the use of synthetic intermediates to test their biological activity.
  2011 Critical Comment: New Details on Legume-Rhizobial Symbioses
  Petra R. A. Kohler, Jasmine Y. Zheng, Elke Schoffers, and Silvia Rossbach; "Inositol Catabolism, a Key Pathway in Sinorhizobium meliloti for Competitive Host Nodulation." Applied and Environmental Microbiology2010, 76 (24), 7972-7980.

Elke Schoffers, Sing R. Gurung, Petra R.A. Kohler, Silvia Rossbach; Chemical synthesis of scyllo-inosamine and catabolism studies in Sinorhizobium meliloti. Bioorganic & Medicinal ChemistryVolume 16, Issue 1615 August 2008, Pages 7838-7842.

  2. 1,10-Phenanthroline as a Template for Catalyst and Sensor Design:
The heavy use of pesticides is causing increased concern among scientists. Many pesticides are phosphate derivatives, so are several chemical warfare agents. In recent years, we have focused on heterocyclic compounds such as 1,10-phenanthroline and related bridged bipyridyl derivatives. They are functionalized and studied as potential chemical sensors and as ligands for transition-metal catalyzed reactions. This project links synthesis to analytical, inorganic, and organometallic chemistry.
  Lars Kohler, Elke Schoffers, Erin Driscoll, Matthias Zeller and Carla Schmiesing “First isolation of disubstituted cis-5,6-dihydro-1,10-phenanthrolines. Lipase-mediated resolution of cis and trans phenoxy alcohol isomers and assignment of absolute stereochemistry via CD and NMR” Chirality , 2012, 24 (3), 245-251.
  Elke Schoffers, Lars Kohler; "Efficient alcoholysis of 5,6-dihydro-1,10-phenanthroline-5,6-epoxide with ytterbium(III) triflate and subsequent enantioselective transesterification with lipases." Tetrahedron: Asymmetry2009, 20, 1897-1902.
  Schoffers, E.; Tran, S. D.; Mace, K. “Preparation of Chiral 5,6-trans-Disubstituted Phenanthrolines From Phenanthroline-5,6-epoxide” Heterocycles 2003, 60, 769-772.
  Schoffers, E. “Reinventing Phenanthroline Ligands” European Journal of Organic Chemistry 2003, 1145-1152.
  Additional Research Information
  Research Openings here
  Research Publications and Presentations here
  Meet the Research Group here
  Group News here
  Dr. Schoffers' Vita here
  Email Dr. Schoffers here