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A new metal-based method to synthesize C(1)-substituted glycals has been developed. Starting with the obtained substituted C-glycals, the possibility of a stereocontrolled addition (via azidoselenation) to form β-C-substituted-2-aminoglycosides has been investigated. Instead of forming the expected C-glycosyl derivatives of 2-amino sugars, an inseparable mixture of diastereomers, which were derived from the corresponding C(1)-allylated glycals, has been obtained.

Copper diethyldithiocarbamate [Cu(DDC)2] complex formed by disulfiram (DSF) and copper ions is a promising therapeutic agent for cancer treatment. However, the poor aqueous solubility of Cu(DDC)2 limited its clinical application. In our previous studies, we developed a stabilized metal ion ligand complex (SMILE) method to prepare Cu(DDC)2 nanoparticle (NP) as an injectable formulation with high drug concentration and excellent physicochemical properties. Our initial in vitro studies also demonstrated its potent anticancer activities. In the current study, we extensively investigated the in vitro anticancer activities of Cu(DDC)2 NP and demonstrated that it could kill drug-resistant prostate cancer cells by inducing non-apoptotic cell death. Further, Cu(DDC)2 NP effectively inhibited the tumor growth in an in vivo paclitaxel-resistant tumor model. In addition, we also performed studies to explore the mechanism of overcoming drug resistance by Cu(DDC)2 NP. Our results showed that Cu(DDC)2 NP did not affect the P-gp activity or change the level of P-gp proteins. It overcomes drug resistance because it is not a substrate of P-gp. Therefore, the use of Cu(DDC)2 NP will not affect the normal function of P-gp and avoid the toxic side effects associated with P-gp inhibitors. It will be a promising therapeutic agent for treating drug-resistant prostate cancers or other solid tumors.

Energy and environment are vital to every aspect of our daily lives. It is paramount to have a new source of energy before the exhaustion of fossil fuels to prevent a setback in the standard of living in which we have grown accustomed to and to have emission of greenhouse gases under control to deflect tremendous global ecological tragedy. Photocatalysis using solar energy is considered by many as the most promising solution for both energy and environment. Among all the photocatalysts under research, titanium dioxide (TiO2) remains one of the most studied for decades. Reducing its bandgap via doping is crucial to harvest visible-light, which accounts for 48% of the total solar energy. In addition, it is very important to keep the particle size small to avoid recombination of the photo-generated electrons and holes.In this dissertation, metal and / or non-metal elements have been used as dopants to modify the electronic structure of TiO2. Special synthesis techniques have been chosen so that the particle size is in the nano-regime. Various techniques such as X-ray diffraction patterns (XRD), Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy (UV-DRS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) have been used to obtain detailed information of the crystal structure, light-absorbing property, organic remains, particle appearance, size distribution and elemental compositions, respectively. Based on the characterization results, we have successfully introduced doping levels into TiO2 to reduce its band gap and thus made the prepared materials visible-light reactive. The sizes of the products are controlled in nano-scale. For all the photocatalysts tested, the performance for the decomposition of methylene blue can be ranked as follows: Ga,N-TiO2 > N-TiO2 > Co,N-TiO2 > Fe-TiO2 Fe,N-TiO2. Furthermore, there have been other important discoveries such as the observation of phenomena similar to that of nitrogen fixation in the Fe-TiO2 experiment and the observation of the surprising reducing properties of commercial material Cab-o-sil.