TY  - JOUR
AU  - Ahmed, M.
AU  - Ganesan, A.
AU  - Wang, F.
AU  - Feyer, V.
AU  - Plekan, O.
AU  - Prince, K. C.
TI  - Photoelectron Spectra of Some Antibiotic Building Blocks: 2-Azetidinone and Thiazolidine-Carboxylic Acid
JO  - The journal of physical chemistry <Washington, DC> / A
VL  - 116
SN  - 1089-5639
CY  - Washington, DC
PB  - Soc.
M1  - PreJuSER-112080
SP  - 8653 - 8660
PY  - 2012
N1  - We wish to thank Professor D. P. Chong for his assistance in the Delta DFT calculations. M.A. and A.G. acknowledge the Swinburne University Postgraduate Research Award (SUPRA) and the Australian Research Council (ARC) for scholarship support. The National Computational Infrastructure (NCI) at the Australian National University under the Merit Allocation Scheme (MAS), the Victorian Partnership for Advanced Computing (VPAC), and Swinburne University Supercomputing Facilities are acknowledged. We acknowledge the Australian Synchrotron for travel funding under the International Synchrotron Access Program (ISAP) and Sincrotrone Trieste (Elettra) for beamtime allocation. We thank our colleagues at Elettra for providing good quality synchrotron light.
AB  - X-ray photoelectron spectra of the core and valence levels of the fundamental building blocks of β-lactam antibiotics have been investigated and compared with theoretical calculations. The spectra of the compounds 2-azetidinone and the 2- and 4-isomers of thiazolidine-carboxylic acid are interpreted in the light of theoretical calculations. The spectra of the two isomers of thiazolidine-carboxylic acid are rather similar, as expected, but show clear effects due to isomerization. Both isomers are analogues of proline, which is well-known to populate several low energy conformers in the gas phase. We have investigated the low energy conformers of thiazolidine-4-carboxylic acid theoretically in more detail and find some spectroscopic evidence that multiple conformers may be present. The measured valence levels are assigned for all three compounds, and the character of the frontier orbitals is identified and analyzed.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:22799571
UR  - <Go to ISI:>//WOS:000307749000027
DO  - DOI:10.1021/jp302950y
UR  - https://juser.fz-juelich.de/record/112080
ER  -