Controlled variations of the physiochemical properties of environmentally benign ionic liquids (ILs) influence the process chemistry of nucleosides. This has been seen in our studies with imidazolium-based new ionic liquids, and the IL methodology successfully employed to synthesize a host of nucleoside analogs currently in use as anti viral drugs. Similarly, synthesized coumarin compounds that show anti tumor activity on human cell lines were synthesized using Lewis acid in ionic liquids. Here, milder conditions were effective for synthesis of these compounds as compared to the conventional methods where strong acid catalysts (e.g. H2SO4, H3PO4, CF3COOH etc.) and high temperatures are required.

In another effort, modification of sodium montmorillonite a cationic clay, has been carried out with pyridinium and imidazolium-based ionic liquids. Our data show an overall increase in interlamellar spacing and improved thermal stability as compared to commercial nanoclays modified with long chain quaternary ammonium salts. This is due to Na+ exchange with cations of the ionic liquids. Utility of the modified montmorillonites has been tested in the preparation of polypropylene nanocomposites. This approach is effective in preparation of biomaterials for the delivery of important therapeutics, illustrated here with representative examples.

Acknowledgment:

Funded by NCI Contract N01-CO-12400