Synthesis, Structure, and Biological Evaluation of Novel N- and O-Linked Diinositols Bernhard J. Paul, Jerremey Willis, Theodore A. Martinot, Ion Ghiviriga, ² Khalil A. Abboud, and Tomas Hudlicky* Contribution from the UniVersity of Florida, Department of Chemistry, PO Box 117200, GainesVille, Florida 32611 Received April 15, 2002 Abstract: Several O-and N-linked inositols and/or aminoinositols have been prepared by iterative opening of epoxides and aziridines derived from homochiral cyclohexadiene cis-diols. The three inositols and their intermediate conduritols (conduramines) were tested against several glycosidases (R- and -glucosidase, R- and -galactosidase, R- and -mannosidase) in an assay that measured the rate of hydrolysis of p-nitrophenolglycosides rather than the concentration of p-nitrophenolate. Somewhat surprisingly, the best inhibition was seen against -galactosidase with several of the compounds. The inositols linked through oxygen or nitrogen were subjected to calcium binding studies performed in NMR experiments. Detailed analysis of the title compounds by NMR spectroscopy has been performed, and full assignments were made. One of the attendant benefits of the preparation of these compounds has been expressed in the design and synthesis of new salen catalysts whose effectiveness has been compared with Jacobsen’s catalyst in the epoxidation of styrene. Introduction Investigations of the biological function of sugars have witnessed enormous progress over the last several years, and cellular processes such as recognition events are now more understood, allowing for the development of carbohydrate-based drugs. 1 Unnatural derivatives of carbohydrates have been at the forefront of bioorganic chemistry research primarily because of their ability to mimic the structure of monosaccharides and hence serve as inhibitors of glycosidases. Since these enzymes are involved in a variety of different biological processes, such research naturally leads to potential applications in the treatment of diabetes, 2 viral infections, 3 and cancer. 3 Recent literature presents many examples of simple carbo- hydrates in which the oxygen has been replaced with carbon (pseudosugars), 4 nitrogen (iminosugars), 5,6 sulfur, 7 and other atoms or groups. 8 Along with polyhydroxylated alkaloids, 9 most such derivatives show modest to excellent inhibition of the common glycosidases that would be involved in the initial steps of cell penetration by the viral material. Similarly, disaccharides and even oligosaccharides have been modified 10 and studied further for their role in the inhibition of glycosidases. Several years ago we disclosed the preparation of a series of simple oligomers containing the configuration of L-chiro-inositol as shown by the general structure 1, Figure 1. 11 The initial reason for investigating such compounds was based on the assumption that O-linked oligomers of this type may play a role in insulin mediation 12 and at the same time not be sensitive to the gastric environment, thus being potential candidates for orally admin- istered medicines. A number of oligomers have been prepared, 13 and some of these compounds proved to have interesting metal chelating properties 14 and displayed tertiary structures in solid state. In an effort to investigate compounds that would mimic the * Address correspondence to this author. E-mail: hudlicky@chem.ufl.edu. ² To whom correspondence regarding NMR spectroscopy should be addressed. To whom correspondence regarding X-ray crystallography should be addressed. (1) (a) Dwek, R. A. Chem. ReV. 1996, 96, 683-720. (b) Yarema, K. 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Published on Web 08/10/2002 10416 9 J. AM. CHEM. SOC. 2002, 124, 10416-10426 10.1021/ja0205378 CCC: $22.00 © 2002 American Chemical Society