Contacts:
Supervisor(s):
Prof. Gloria Uccello Barretta
Title of the PhD project:
Chiral analysis by NMR spectroscopy
Abstract of the PhD project:
Divergent pharmacological behaviour of several enantiomers of chiral active ingredients still represents a critical aspect in biomedical and pharmaceutical researches, which gave great impulse to the development of sophisticated procedures of quantification of enantiomers, chromatographic and spectroscopic mainly. Among spectroscopic methods, nuclear magnetic resonance (NMR) methods are based on the use of chiral auxiliaries able to transfer enantiomeric substrates into a diastereoisomeric environments, thus making distinguishable their NMR parameters. Among chiral auxiliaries for NMR, chiral solvating agents (CSAs) have emerged for their best practicality of use and favourable spectroscopic features. Proposed chiral solvating agents span from very simple low molecular weight compounds, to natural products or systems with highly preorganized structures. The rational design of new efficient and versatile chiral auxiliaries requires the knowledge of molecular basis of enantiodiscrimination. Nuclear Magnetic Resonance (NMR) spectroscopy invests thoroughly all the most important aspects of molecular and chiral recognition phenomena. The project focuses on the development of new chiral auxiliaries for the differentiation of enantiomeric substrates by NMR and on the comprehension of the origin of chiral recognition phenomena originated by different classes of chiral receptors. Three main classes of chiral auxiliaries will be considered:
- Polyamidic systems with particular reference to thiourea derivatives of single commercially available chiral platforms;
- Macrocyclic systems, mainly cyclodextrins, to be used in their native forms or subjected to suitable derivatization procedures;
- Natural products, like chincona alkaloids.
Publications:
• Cesari, A.; Recchimurzo, A.; Fabiano, A.; Balzano, F.; Rossi, N.; Migone, C.; Uccello-Barretta, G.; Zambito, Y.; Piras, A.M. Improvement of Peptide Affinity and Stability by Complexing to Cyclodextrin-Grafted Ammonium Chitosan.
Polymers 2020, 12, 474.
• Recchimurzo, A.; Micheletti, C.; Uccello-Barretta, G.; Balzano, B. Thiourea Derivative of 2-[(1R)-1-Aminoethyl]phenol: A Flexible Pocket-like Chiral Solvating Agent (CSA) for the Enantiodifferentiation of Amino Acid Derivatives by NMR Spectroscopy. J. Org. Chem. 2020, 85, 5342-5350.
Oral communications at conferences:
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Poster communications at conferences:
• Alessandra Recchimurzo, Anna Maria Piras, Andrea Cesari, Angela Fabiano, Federica Balzano, Ylenia Zambito, Gloria Uccello Barretta. “2-Methyl-β-cyclodextrin conjugates of ammonium-chitosans: affinity towards Dalargin and protection against enzymatic hydrolysis”. 4th International Summer School of cyclodextrins, June 10th-12th 2019, Milan (Italy).
• Alessandra Recchimurzo, Andrea Cesari, Federica Balzano, Ylenia Zambito, Gloria Uccello Barretta, “Mucoadhesivity of thiolated ammonium-chitosans and their nanoaggregates by NMR spectroscopy”. Chemistry For the Future 2019, July 3rd - 5th 2019, Pisa (Italy).
• Alessandra Recchimurzo, Anna Maria Piras, Andrea Cesari, Angela Fabiano, Federica Balzano, Ylenia Zambito, Gloria Uccello Barretta, “Affinity of hexapeptide Dalargin towards cyclodextrin conjugates of ammonium-chitosans”. Innovative Researches in Pharmaceutical and Environmental Science, November 27th 2019, Pisa (Italy).
Other achievements:
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