With the support of the Organic and Macromolecular Chemistry Program, Profesor Stephen DiMagno, of the Department of Chemistry at the University of Nebraska - Lincoln, is developing `polar hydrophobicity` in the design of fluorinated hosts and guests for molecular recognition. Through the synthesis and study of heavily fluorinated carbohydrate analogs incorporating multiple CF2 (for CHOH) substitutions, Professor DiMagno tests the hypothesis that preorganized sites and bound guests are `harder` than equivalent structures in solution due to the decreased importance of energetic terms arising from electron polarization. The polar hydrophobic effect results from the peculiar physical characteristics of the carbon-fluorine bond, which is at once both extremely polar and hydrophobic. Since the polar characteristics of the C-F bond dominate in crystalline or organized phases while hydrophobic effects are more important in solution, both enthalpic and entropic factors may be more favorable for binding fluorinated analogs than natural substrates. Thus, these studies are expected both to demonstrate the use of polar hydrophobicity as a tool for the design of hosts and guests and to contribute to the general understanding of molecular recognition and hydrogen bonding. The specific recognition and binding of one molecule by another forms the basis of a myriad of chemical and biochemical phenomena. With the support of the Organic and Macromolecular Chemistry Program, Professor Stephen DiMagno, of the Department of Chemistry at the University of Nebraska - Lincoln, is developing the concept of `polar hydrophobicity` in order to design new classes of `hosts` and `guests` for molecular recognition. Professor DiMagno's studies focus on the peculiar physical characteristics of the carbon-fluorine bond, which is at once both extremely polar and highly hydrophobic (water-hating). Through the study of sugar derivatives in which polar and hydrophilic (water-loving) groups are replaced by fluorine atoms, Professor DiMagno obtains information about the roles of polarity and hydrophobic interactions in molecular recognition events, gaining both practical knowledge about the design of new `hosts` and `guests` for general molecular recognition studies as well as detailed information about the biological recognition of natural substrates.
