Surya Adhikari recently completed his PhD in organic chemistry from University of Toledo. His research was focused towards gold catalyzed glycosylation and synthesis of digitoxin analogs.
Congratulations Dr. Adhikari and best wishes to your future career. He has published several research articles and is moving to IUPUI-Indianapolis from August.
Below is a brief description of his research work while he was in Toledo.
Oligosaccharides and glycoconjugates are one of the important classes of compound in biological chemistry. Carbohydrates play important roles not only in several biological processes but also are important constituent of many natural products and drugs. Oligosaccharides, a class of biopolymers unlike nucleotides, which are linear polymers, contain several positions linked to another sugars or any other molecules. This type of combination would increase the possible number of unique polymers. For instance, three different nucleotides or amino acids can only generate six trimers, while three different hexoses could generate up to 27,648 unique tri-saccharides. To unveil the biological roles of oligosaccharides, large amounts of fairly pure oligosaccharides are required; however, carbohydrates are notoriously difficult to isolate from natural sources and often times only available in very small quantities. Despite numerous glycosylation protocols have been developed, synthesis of complex oligosaccharide remains very challenging. Building structurally defined oligosaccharides is the most important duty to study the function and structure of complex glycans. The inherent nature of the leaving group at anomeric carbon principally determines the mode of action in the glycosylation.
Most of these glycosylations involve activation of leaving group with stoichiometric amount of the promoter for the departure of the leaving group. Dr. Adhikari's approach involved catalytic amount of activator to access the desired disaccharides. In the second part of his research, he synthesized different analogs of digitoxin. The bioactivity of those analogs will be disclosed in due course from our research group.