title: Structural Elucidation of β-Lactam Diastereoisomers through Ion Mobility Mass Spectrometry Studies and Theoretical Calculations.
abstract: The ion mobility combined with mass spectrometry and theoretical calculations were used to characterize and separate six diastereoisomeric β-lactams. The influence of traveling wave height and wave velocity, size of the alkali metal ion (Li(+), Na(+) and K(+)) and drift gases with varying masses and polarizabilities (N2 and CO2) on separation efficacy was additionally examined. The best separation of diastereoisomers of β-lactams was observed for adducts with Na(+) and Li(+) ions, whereas other parameters had little impact on separation process. The isomeric β-lactams were characterized by both experimental and theoretical collision cross sections. The theoretically calculated values of collision cross sections obtained from extensive molecular dynamics and density functional theory calculations for model structures agreed well with those established experimentally. The relationship between separation efficacy and the configuration at the carbon atoms C5 and C6 of β-lactam ring was defined.
authors.affiliation: Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Troć
authors.affiliation: Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Zimnicka
authors.affiliation: Mossakowski Medical Research Centre, Polish Academy of Sciences, Bioinformatics Laboratory, Pawińskiego 5, 02-106, Warsaw, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Koliński
authors.affiliation: Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
authors.forename: Witold
authors.initials: W
authors.lastname: Danikiewicz
mesh_terms: D000465:Algorithms; D002245:Carbon Dioxide / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D008672:Metals, Alkali / Q000737:chemistry; D008958:Models, Molecular; D009584:Nitrogen / Q000737:chemistry; D013237:Stereoisomerism; D047090:beta-Lactams / Q000737:chemistry*
chemical_list: D007477:Ions; D008672:Metals, Alkali; D047090:beta-Lactams; D002245:Carbon Dioxide; D009584:Nitrogen
keywords: DFT; IM-MS; alkali metals cations; diastereoisomer differentiation; ion mobility mass spectrometry; theoretical calculations; β-lactams