Fall 2019 Seminars

 

Lunch at 12 PM (Grote 403)/Seminar at 3 PM (Grote 411, Presentation 3-3:45 PM & Question Sesssion 3:45-4:00 PM)

November 15 seminar will take place in Grote 131 at 3:00 pm.

 

 

Date Speaker Home Institution Host Type of Chemistry
August 23, 2019 First Day No Speaker First Day No Speaker First Day No Speaker First Day No Speaker
         
August 30, 2019        
         
September 6, 2019 Dr. Sivarao Digavalli ETSU Dr. Yang Pharmacy
         
September 13, 2019        
         
September 20, 2019 Dr. Robert J. Gilliard, Jr. UVA Dr. Pienkos Inorganic
         
September 27, 2019 Dr. Konstantinos D. Vogiatzis UTK Dr. Albu Computational
         
October 4, 2019        
         
October 11, 2019 URP Poster Session No Speaker URP Poster Session No Speaker URP Poster Session No Speaker URP Poster Session No Speaker
         
October 18, 2019        
         
October 25, 2019 SERMACS No Speaker SERMACS No Speaker SERMACS No Speaker SERMACS No Speaker
         
November 1, 2019        
         
November 8, 2019        
         
November 15, 2019 Dr. Robert Mebane UTC Dr. Rybolt Organic & Historical
         
November 22, 2019 Dr. Abbas G. Shilabin ETSU Dr. Yang Medicinal chemistry & Natural products
         
November 29, 2019 Thanksgiving No Class Thanksgiving No Class Thanksgiving No Class Thanksgiving No Class

 

 

Dr. Sivarao Digavalli (East Tennessee State University)

Timing is of the essence: Neural oscillatory deficits in schizophrenia and an opportunity for rational drug development

Abstract:  Schizophrenia is a troubling mental illness that affects about 1% of the population.  The illness strikes individuals in their youth and severely distorts their experience of reality. Thus, patients may hear voices (hallucinations) instructing them with bizarre orders, may get worried about an agency or individual spying on them (delusions) without evidence etc. Additionally, they suffer from cognitive and social disabilities that impact their everyday living.  Current pharmacological therapy for schizophrenia is inadequate and there is a need for better therapies.  Brain’s electrical activity, reflecting physiological function in large networks of neurons, can be recorded using the technique of electroencephalography (EEG) in humans as well as in experimental animals.  When a series of clicks are presented at a particular frequency, regions in the brain get entrained to the stimulus and show oscillations at the driving frequency.  In schizophrenia, this entrainment is poor, especially if the driving frequency is around 40 Hz (gamma frequency).  We use such experimental models to predict and test the response of new drugs that can eventually improve treatment options.

 

Dr. Robert J. Gilliard, Jr. (Department of Chemistry, University of Virginia)

Novel Redox Chemistry of the Main Group Elements: From Subvalent Organometallics to Molecular Materials

Abstract:  Research efforts in the Gilliard laboratory span diverse areas of chemical synthesis related to the activation of inert chemical bonds, energy storage and release, and molecular hybrid materials chemistry. Our work with s-block metals has resulted a number of advances in the subvalent and hydridic chemistry of the alkaline earth metals (e.g., beryllium, magnesium, calcium), including molecular models for hydrogen storage. Recently, we have begun to study main group element-doped heterocycles related to the development of hybrid molecular materials. Our primary goal has been to access and study the optical properties of main group elements in uncommon electronic states within conjugated molecules. This presentation will highlight key research studies but will also provide an introduction to the graduate program at the University of Virginia.

 

Dr. Konstantinos D. Vogiatzis (Department of Chemistry, University of Tennessee, Knoxville)

Coupling Quantum Chemistry with Machine Learning

The current post-combustion carbon capture process at coal plants uses aqueous amine solvents, such as monoethanolamine (MEA), to effectively bind CO2. Regenerating the solvent is energetically expensive, and it is estimated that this process would utilize nearly 20-30% of the power that a coal plant produces, increasing energy prices by as much as 90%. Passive non-porous polymeric membranes offer an alternative, cost-effective technology for CO2 capture. Unlike solvents, dense polymeric membrane gas separations utilize much weaker physisorption interactions. Intermolecular interactions allow the CO2 molecules to diffuse through the membrane while N2 molecules do not interact with the polymeric matrix and do not permeate the membrane, which results in a lower energy cost separation. The interaction of CO2 with the polymer is one of the most important components, where CO2–philicity can be enhanced by introducing in the material certain functional groups (usually, Lewis bases).

We have performed computational studies on individual families of functional groups introduced in the repeating units of polymeric materials. [1-4] For capturing the properties of a larger number of organic molecules, we have developed a novel molecular fingerprinting method based on persistent homology that can encode the geometrical and electronic structure of molecules for chemical applications. [5] Its applicability is demonstrated on noncovalent interactions between functional groups of materials and small gas molecules for environmental applications. Our quantum chemical calculations were performed on a small number of molecules (100-200) for the generation of meaningful data. We have used these data in order to train a statistical model that includes the new fingerprinting method and machine learning algorithms. The trained models have been used for high-throughput virtual screening by predicting the properties of larger molecular databases (more than 100,000 entries) where quantum chemical data are not available. We are currently examining calixarenes, a family of organic oligocycles, that can capture CO2 via host-guest interactions. [6] Recent methodological advances on the acceleration of accurate electronic structure theory computations via machine learning will also be discussed. [7] 

[1] H. Feng, T. Hong, S. M. Mahurin, K. D. Vogiatzis, K. R. Gmernicki, B. K. Long, J. W. Mays, A. P Sokolov, N.-G. Kang, T. Saito Polym. Chem. 2017, 8, 3341-3350.

[2] P.‐F. Cao, B. Li, T. Hong, J. Townsend, Z. Qiang, K. Xing, K. D. Vogiatzis, Y. Wang, J. W. Mays, A. P. Sokolov, T. Saito Adv. Func. Mater. 2018, 28, 1800741.

[3] C. R. Maroon, J. Townsend, K. R. Gmernicki, D. J. Harrigan, B. J. Sundell, J. A. Lawrence III, S. M. Mahurin, K. D. Vogiatzis, B. K. Long Macromolecules, 2019, 52, 1589-1600.

[4] C. R. Maroon, J. Townsend, M. A. Higgins, D. J. Harrigan, B. J. Sundell, J. A. Lawrence III, J. T. O’Brien, D. O’Neal, K. D. Vogiatzis, B. K. Long Submitted.

[5] J. Townsend, C. M. Micucci, J. Hymel, V. Maroulas, K. D. Vogiatzis In Preparation.

[6] J. H. Hymel, J. Townsend, K. D. Vogiatzis Submitted.

[7] J. Townsend, K. D. Vogiatzis J. Phys. Chem. Lett., 2019, 10, 4129.

 

Dr. Rob Mebane (University of Tennessee, Chattanooga)

Raney® Nickel - A Life Changing Catalyst

Most of us come into contact daily with materials made from chemicals whose preparation involved the use of the catalyst known as Raney® nickel. For example, did you use a toothbrush, walk on carpet or ride in a car today? If so then you probably benefited from Raney® nickel. Most toothbrushes use nylon bristles and much of the carpet today is made from nylonfibers. Nylon is also used in the molding of engineered components as a replacement for metallic and other materials in automobiles.

This talk will examine the importance of Raney® nickel as a catalyst and will explore how this catalyst was invented in Chattanooga by Murray Raney.

 

Dr. Abbas G. Shilabin (East Tennessee State University)

Drug Discovery of Bioactive Natural Products and Synthetic Small Molecules

Natural products research continues to be an important cornerstone for drug discovery of bioactive molecules for many decades. Natural products isolated from marine, plants, and microbial environment clearly hold an enormous potential to provide new small-molecule chemical entities introduced as drug leads for the development of various agents with medicinal applications. Advances in both natural products-based screening and NMR techniques for structural assignment have contributed to a revival of interest in bioactive lead compounds from natural sources.

Over the past 20 years, a continuing effort was directed towards the extraction, bioassay-guided isolation, structure elucidation of novel prototypes, as well as structure-activity relationship studies and further optimization of their analogs. Biologically active compounds were further evaluated for their potential activities against recent major therapeutic challenges. The identification of new structural classes was shown to play a key role leading to a better understanding and treatments for the diseases. In particular, chemical transformations have provided a number of promising synthetic and semi-synthetic bioactive compounds that we have identified during our research. The strengths of my research team lie in organic chemistry and natural products chemistry, emphasizing the interface between chemistry and biology. We have been enjoying the utilization of our synthetic chemistry expertise in various aspects of projects including the structure-based design and synthesis of high therapeutic value molecules, natural products isolation and structure assignment of active complex natural products; running rational modifications of promising natural products to increase their potency, reduce their toxicity, or improve their pharmacokinetic properties; and using computational chemistry and modeling studies in computer-aided drug design.

My seminar will cover the following projects:

  • Circumdatin A and B isolated from the fungus Aspergillus ochraceus.
  • Semisynthetic modification and lead optimization of marine natural products,
    Manzamine alkaloids and Kahalalide F.
  • Extraction and purification of biologically active metabolites from the Rhodococcus
  • D-γ-Tocotrienol: A promising radioprotective agent isolated from palm oil.
  • Design and synthesis of bacterial DD-peptidases inhibitors.

Novel and selective CB2 inhibitors for targeting neurodegenerative disorders.