Undergraduate Research Symposium

Department of Chemistry and Biochemistry

College of Charleston

July 23, 1999

103 Education Center

10:00-10:30

Cloning and Overexpression of Ribonucleotide Reductase from Coryneform Ammoniagenes, Mindy Stelling

10:30-10:50

 Surface Energy Density Characterization of the High Energy Bombardment of Silicon and Copper with Xe and SF5 Projectiles, David Ward

10:50-11:00

Break

11:00-11:20

Energy Density Considerations for the Ejection of Stable Organic Molecules from Cu(001) and Si(100) with SF5 and Xe Projectiles, Tai Nguyen

11:20-11:30

The Strong-Base Preparation Of Select Hydroxyaryl-, Pyrazoles And Isoxazoles With Potential For Photophysical Studies, Jessica D. Townsend

11:30-11:40

Break

11:40-11:50

The Condensation Of Polylithiated Phenylacetic Acid Hydrazides With Esters And Other Electrophilic Reagents For The Preparation Of 3h-Pyrazolin-3-Ones And Related Materials, Stefan J. Pastine

11:50-12:00

The Preparation Of New Dihydroisoxazoles From Dilithiated Oximes And Select -Unsaturated Ketones, Wayne Kelley

12:00-12:30

Lunch Break

12:30-12:40

The Preparation And Characterization Of New Heterocyclic Compounds Prepared From Dilithiated 1-Tetralone Or 2-Tetralone, Oximes Or Substituted Hydrazones And A Variety Of Esters, Kelly L. Rose

12:40-12:50 The Preparation Of New 1h-Pyrazoles From Polylithiated C(Alpha),N-Hydrazones And Esters, Deborah A. Schady
12:50-1:00 The Preparation Of 1h-Pyrazole-5-Carboxamides And Isoxazole-5-Carboxamides From Dilithiated Phenylhydrazones Or Dilithiated Oximes And Lithiated Ethyl Oxanilates Or Lithiated Ethyl Oxamate, Jennifer R. Downs

A poster session will be held from 3:00-4:30 in 317 SCIC.

Poster: On the Preparation of Amidoximes from Nitriles, Andrew S. Cornwell, Alap R. Jani and F. J. Heldrich,

Abstract 1:

Cloning and Overexpression of Ribonucleotide Reductase

from Coryneform Ammoniagenes

Mindy Stelling, speaker, Kelby Kizer, poster presenter, Shaun Vincent, and Prof. Pam Riggs-Gelasco, College of Charleston, Charleston, South Carolina 29424-0001

Ribonucleotide reductase catalyzes the critical conversion of ribonucleotides to deoxyribonucleotides in all organisms. Despite its universal importance in DNA synthesis, different organisms have evolved diverse enzymatic cofactors to catalyze this reaction. The enzyme from Cornyform bacteria requires Mn for substrate reduction. Very little is known about this enzyme and its cofactor, since insufficient amounts of protein can be obtained from the native organism. With the recent of the ribonucleotide reductase gene sequence fromC.ammoniagenes, it is now possible to clone and overproduce the enzyme, which will allow production of gram quantities of protein for spectroscopic studies. Evidence of successful cloning and overexpression of this protein in E. coli host cells will be presented.

Mindy Stelling Kelby Kizer

 

Abstract 2:

Surface Energy Density Characterization of the High Energy Bombardment of Silicon and Copper with Xe and SF5 Projectiles

D. Ward, T. Nguyen, J. A. Townes, A. K. White and K. D. Krantzman, College of Charleston, Charleston, South Carolina 29424-0001 and B. J. Garrison, The Pennsylvania State University, University Park, Pennsylvania 16802

The use of polyatomic projectiles in organic secondary ion mass spectrometry has attracted a lot of attention because of the nonlinear enhancement in secondary ion yield that these projectiles produce. Our group has been conducting molecular dynamics simulations in order to better understand the mechanism behind such enhancements. Our studies have focussed on four configurations: SF5-Si, SF5-Cu, Xe-Si, Xe-Cu. The system is composed of a monolayer of 20 biphenyl molecules on two substrates: Cu(001) and Si(100). We use radial plots from the impact point of the energy density distribution for each trajectory to explore a correlation to the yield. A set of criteria consisting of both filters and selection rules are applied to characterize the energy density on the surface of the substrate for each configuration and to isolate the conditions requisite for high and low yield secondary ion emission. A time averaged outward flux of the energy density is employed to characterize each projectile/substrate system. The correlation between high and low yield on a single configuration is well established in our data, and methods of comparing yield between configurations is discussed.

David Ward

Abstract 3:

Energy Density Considerations for the Ejection of Stable Organic Molecules from Cu(001) and Si(100) with SF5 and Xe Projectiles

T. Nguyen, D. Ward, J. A. Townes, A. K. White and K. D. Krantzman, College of Charleston, Charleston, South Carolina 29424-0001 and B. J. Garrison, The Pennsylvania State University, University Park, Pennsylvania 16802

The nonlinear enhancement in yield with polyatomic projectiles has been an area of great interest. In particular, we have studied the activities of Xe and SF5 on two substrates, Cu(001) and Si(100). It is believed that the differences in yields can be attributed primarily to the interactions between the biphenyl molecule and the substrate. To quantify the effects of these interactions, the beneficial energy density below the biphenyl molecule was measured. From this analysis, it was seen that the energy density was more intense on Cu(001), while on Si(100) the energy density was broader. Furthermore, a threshold value for ejection of stable molecules was determined for both substrates.

 

 

 

Abstract 4:

THE STRONG-BASE PREPARATION OF SELECT HYDROXYARYL-, PYRAZOLES AND ISOXAZOLES WITH POTENTIAL FOR PHOTOPHYSICAL STUDIES.

Jessica D. Townsend, Shannon L. Studer-Martinez, and Charles F. Beam,

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

Several ortho-hydroxyaryl-, oximes, or phenylhydrazones, or carbomethoxyhydrazones made from ortho-hydroxyacetophenone and related compounds were trilithiated with excess lithium diisopropylamide followed by condensation with a variety of substituted benzoate esters, such as ethyl para-aminobenzoate or methyl para-chlorobenzoate, to give C-acylated intermediates that were not isolated but cyclized directly with aqueous acid to substituted ortho-hydroxylaryl-, isoxazoles, N-phenylpyrazole, or N-carbomethoxypyrazoles.

The products were characterized by FT-IR, H-1 NMR, and C-13 NMR. Many of the compounds prepared were also given UV-vis absorption and florescence studies because of their potential for excited state intramolecular proton transfer.

Jessica Townsend

Abstract 5:

THE CONDENSATION OF POLYLITHIATED PHENYLACETIC ACID HYDRAZIDES WITH ESTERS AND OTHER ELECTROPHILIC REAGENTS FOR THE PREPARATION OF 3H-PYRAZOLIN-3-ONES AND RELATED MATERIALS.

Stefan J. Pastine, Wayne Kelley, Jr., Heather A. Greer, Jessica D. Townsend, Kelly L. Rose, Deborah A. Schady, Jennifer R. Downs, and Charles F. Beam,

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

 

Phenylacetic acid phenylhydrazides were readily prepared, and they were polylithiated in excess lithium diisopropylamide followed by condensation with a variety of benzoate esters. The C-acylated intermediates were not isolated, but cyclized immediately with aqueous acid to afford 2,3-dihydro-3H-pyrazolin-5-ones. All of the compounds were characterized by FT-IR, H-1 NMR, and C-13 NMR, with additional support from combustion analysis. An X-ray crystallographic analysis of a single compound in this series ia planned.

The potential of the introductory strong-base synthesis involving these polylithiated intermediates will be presented.

Stefan Pastine

Abstract 6:

THE PREPARATION OF NEW DIHYDROISOXAZOLES FROM DILITHIATED OXIMES AND SELECT a,b-UNSATURATED KETONES.

Wayne Kelley, Jr., Kelly L. Rose, Deborah A. Schady, Heather A. Greer, Jessica D. Townsend, Jennifer R. Downs, Stefan J. Pastine, and Charles F. Beam,

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

A variety of C(alpha),O-oximes were dilithiated or polylithiated with lithium diisopropylamide, and the resulting dianion-type intermediates were treated with ketones, such as trans-chalcone, or to give intermediates that were not isolated, but were acid cyclized directly with aqueous acid to give substituted dihydroisoxazoles (2-isoxazolines). All of the new compounds were characterized by FT-IR, H-1 NMR, and C-13 NMR, with additional support from combustion analysis.

 

The potential of the introductory or continuing strong-base synthesis involving these polylithiated intermediates will be presented.

Wayne Kelley

Abstract 7:

THE PREPARATION AND CHARACTERIZATION OF NEW HETEROCYCLIC COMPOUNDS PREPARED FROM DILITHIATED 1-TETRALONE OR 2-TETRALONE, OXIMES OR SUBSTITUTED HYDRAZONES AND A VARIETY OF ESTERS.

Kelly L. Rose, Deborah A. Schady, Wayne Kelley, Jr., Heather A. Greer, Jessica D. Townsend, Jennifer R. Downs, Stefan J. Pastine, Shannon L. Studer-Martinez, and Charles F. Beam,

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

Several tetralone (1- and 2-) hydrazones or oximes were dilithiated with excess lithium diisopropylamide, followed by condensation with esters to give C-acylated intermediates that were not isolated, but were acid cyclized to afford substituted dihydrobenzindazoles or dihydronaphthisoxazoles. All of the new compounds were characterized by FT-IR, H-1 NMR, and C-13 NMR, with additional support from combustion analysis.

The potential of the introductory or continuing strong-base synthesis involving these polylithiated intermediates will be presented.

Professor Beam, Kelly Rose

Abstract 8:

THE PREPARATION OF NEW 1H-PYRAZOLES FROM POLYLITHIATED C(ALPHA),N-HYDRAZONES AND ESTERS

Deborah A. Schady, Stefan J. Pastine, Jennifer R. Downs, Jessica D. Townsend, Kelly L. Rose, Wayne Kelley, Jr., Heather A. Greer and Charles F. Beam

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

A variety of polylithiated C(alpha),N-hydrazones (N-phenyl, N-tosyl) were treated with electrophilic reagents, that included methyl 2-(aminosulfonyl)benzoate and methyl 2-phenylquinolinecarboxylate and others to afford C-acylated intermediates that were not usually isolated, but cyclized directly to the new 1H-pyrazole. The Shapiro reaction did not occur in the few successful cases involving polylithiated C(alpha),N-tosylhydrazones. All of the new compounds were characterized by FT-IR, H-1 NMR, and C-13 NMR, with additional support from combustion analysis.

The potential of the continuing long term strong-base syntheses involving these polylithiated and related polylithiated intermediates will be presented.

Deborah Schady

Abstract 9:

THE PREPARATION OF 1H-PYRAZOLE-5-CARBOXAMIDES AND ISOXAZOLE-5-CARBOXAMIDES FROM DILITHIATED PHENYLHYDRAZONES OR DILITHIATED OXIMES AND LITHIATED ETHYL OXANILATES OR LITHIATED ETHYL OXAMATE.

Jennifer R. Downs, Deborah A. Schady, Stefan J. Pastine, Jessica D. Townsend, Kelly L. Rose, Wayne Kelley, Jr., Heather A. Greer, and Charles F. Beam

Department of Chemistry and Biochemistry, College of Charleston, Charleston, SC 29424

The preliminary study has involved treating the dilithiated (1,4-dianions) phenylhydrazones or oximes with either lithiated ethyl oxanilates, or lithiated ethyl oxamate to give intermediates that were quenched with acid and separately cyclized with acid using a water trap to give new 1H-pyrazole-5-carboxamides or isoxazole-5-carboxamides.

The potential of the continuing long term strong-base syntheses involving these polylithiated and related polylithiated intermediates will be presented.

Jennifer Downs

Abstract 10:

On the Preparation of Amidoximes from Nitriles

Andrew S. Cornwell, Alap R. Jani and F. J. Heldrich,

College of Charleston, Charleston, South Carolina 29424-0001

There are two goals of this project: to determine that amidoxime functionality can be isolated from aryl cyanides with quaternary ammonium salt side chains, and to determine if the amidoxime functionality is biologically equivalent to amidine functionality currently used in study of retrograde axonal transport. The current amidine RATFIA (retrograde axonal transport fluorescent imaging agents) compounds available pose synthetic difficulty, are poorly soluble in an aqueous environment, and have high levels of toxicity in vivo. It is hoped that the new compounds will improve on all of these qualities and maintain the desired functions of imaging agents.

Professor Heldrich, Andrew Cornwell