Synthesis of nanomaterials with novel optical properties; synthesis and characterizaton of functionalized nanomaterials for applications in drug delivery, diagnostics and vaccine development; total synthesis of heterocyclic natural products, development of methodology for organic synthesis, mechanistic organometallic chemistry, synthesis of complex oligosaccharides and glycoprotein derivatives, chemistry of hypervalent silicon derivatives.
Major Recognitions and Honors
Significant Professional Service and Activities
In addition to his academic position, Dr. DeShong is the founder and Chief Scientific Officer of SD Nanosciences, Inc. of Beltsville, MD. The focus of the company is to develop novel methods for the detection and treatment of pathogenic infections and cancer. Dr. DeShong has consulted for >15 companies on problems related to synthetic and pharmaceutical chemistry.
Dr. DeShong has supervised the Ph.D. and Masters theses of > 50 graduate students. In addition, 10 postdoctorals and >50 undergraduates have performed research in his laboratory.
Applications of the carbohydrate technology to the the preparation of functionalized nanomaterials for vaccine development, diagnostics and drug delivery are underway. This multidisciplinary collaboration with materials engineers and cell biologists (Drs. Stein and Lee in Cell Biology & Molecular Genetics, English at Wichita State, Zachariah in Chemical Engineering, and Vogel at the UM School of Medicine) has demonstrated that nanostructures derived from catanionic surfactant vesicles, gold, and porous silica with interesting morphologies and/or properties can be functionalized with complex oligosaccharide and peptide conjugates that impart a variety of unique characteristics to the functionalized nanomaterial. First, these coatings typically result in the
formation of materials that are stable in biological fluids indefinitely. In addition, the coatings can be tailored to target the nanostructures to specific cell types resulting in systems that are ideal for vaccine production and drug delivery applications. The focus of our studies are to develop a “Molecular Toolbox” of general methodology for the functionalization of a wide variety of materials, to synthesize oligosaccharide conjugates that will “target”specific cell populations (pathogens and tumors), and to measure the release profiles of the functionalized nanomaterials.
A. TEM image of porous silica nanoparticles coated with oligosaccharide cell surface conjugates. B. Hollow silica nanoparticles. C. Confocal microscope image of porous silica nanoparticles filled with antitumor antibiotic doxorubicin.
Another area of research in Professor DeShong’s group focuses on development of new strategies for the stereoselective synthesis of heterocyclic systems and the application of these approaches to the preparation of natural products and biologically active substances. The DeShong group has demonstrated that hypervalent silicates can be employed for carbon-carbon bond couplings employing palladium catalysis. This coupling strategy that is similar to Suzuki (boron compounds) and Stille (tin compounds) couplings has been employed f or the synthesis of unsymmetrical biaryls and allylic
couplings. Applications of this strategy to the synthesis of antimitotic agents colchicine and pancratistatin have been recently reported. Utilization of the siloxane coupling methodology to the total synthesis of streptonigrin is underway.