We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Properties of Gaseous Deprotonated L-Cysteine S-Sulfate Anion [cysS-SO 3 ] − : Intramolecular H-Bond Network, Electron Affinity, Chemically Active Site, and Vibrational Fingerprints.
- Authors
Wang, Qiaolin; Qin, Zhengbo; Hou, Gao-Lei; Yang, Zheng; Valiev, Marat; Wang, Xue-Bin; Zheng, Xianfeng; Cui, Zhifeng
- Abstract
L-cysteine S-sulfate, Cys-SSO3H, and their derivatives play essential roles in biological chemistry and pharmaceutical synthesis, yet their intrinsic molecular properties have not been studied to date. In this contribution, the deprotonated anion [cysS-SO3]− was introduced in the gas phase by electrospray and characterized by size-selected, cryogenic, negative ion photoelectron spectroscopy. The electron affinity of the [cysS-SO3]• radical was determined to be 4.95 ± 0.10 eV. In combination with theoretical calculations, it was found that the most stable structure of [cysS-SO3]− (S1) is stabilized via three intramolecular hydrogen bonds (HBs); i.e., one O−H⋯⋯N between the –COOH and –NH2 groups, and two N−H⋯⋯O HBs between –NH2 and –SO3, in which the amino group serves as both HB acceptor and donor. In addition, a nearly iso-energetic conformer (S2) with the formation of an O−H⋯⋯N−H⋯⋯O−S chain-type binding motif competes with S1 in the source. The most reactive site of the molecule susceptible for electrophilic attacks is the linkage S atom. Theoretically predicted infrared spectra indicate that O−H and N−H stretching modes are the fingerprint region (2800 to 3600 cm−1) to distinguish different isomers. The obtained information lays out a foundation to better understand the transformation and structure–reactivity correlation of Cys-SSO3H in biologic settings.
- Subjects
PHARMACEUTICAL chemistry; PHOTOELECTRON spectroscopy; BIOCHEMISTRY; ISOMERS; INFRARED spectra; ELECTRON affinity; CYSTEINE
- Publication
International Journal of Molecular Sciences, 2023, Vol 24, Issue 2, p1682
- ISSN
1661-6596
- Publication type
Article
- DOI
10.3390/ijms24021682