Paolo Suating

• Organic Chemistry

The Suating Lab works in the field of aqueous organic supramolecular chemistry– the study of the interplay between water, organic co-solutes, and salts, and the energies involved in their interactions. We use synthetic macrocycles called resorcinarenes that can be used as simple scaffolds to probe specific supramolecular phenomena such as electrostatics and hydrophobicity. Resorcinarenes are relatively simple molecules: they are formed from the acid-catalyzed condensation of resorcinol and an aldehyde, and have fourfold rotational axis and vertical mirror planes (C_4v symmetry group).

The first project aims to gain insight into the fundamental forces that govern the formation of protein aggregates that are implicated in disease, such as Alzheimer’s, Parkinson’s, and prion diseases, and the effects of salts on these processes. By carefully choosing the starting aldehyde, we can attach polypeptide chains to the resorcinarene to mimic certain regions of the more complex polypeptides. These chains not only give the macrocycle water solubility, but they also form a polar, hydrated pocket for binding salts in water. These salts can influence the solubility of the molecule (the Hofmeister effect) and have the potential to give aggregates that are either disordered (precipitation) or have long-range order (crystallization).

The goal of the second project is to explore the practical applications of surface chirality to separation science by exploiting the hydrophobic effect—why oil and water don’t mix. Resorcinarenes by their nature, are achiral. Recent literature have described efforts to post-synthetically de-symmetrize resorcinarenes for asymmetric catalysis. We aim to perform bottom-up syntheses that will give macrocycles that have inherent chirality via rotational asymmetry (M or P designations). The hydrophobic surface of the formed macrocycle can then potentially bind selectively to one enantiomer in a racemic mixture of apolar organic molecules without introducing any covalent linkers between the macrocycle and the bound molecule.

Students in the research group will learn not only synthetic techniques, but also a variety of analytical techniques such as NMR spectroscopy, UV-vis and fluorescence spectroscopy, mass spectrometry, and isothermal titration calorimetry.

• Suating, P.; Kimberly, L. B.; Ewe, M. B.; Chang, S. L.; Fontenot, J. M.; Sultane, P. R.; Bielawski, C. W.; Decato, D. A.; Berryman, O. B.; Taylor, A. B.; et al. Cucurbit[8]uril Binds Nonterminal Dipeptide Sites with High Affinity and Induces a Type II β-Turn. J. Am. Chem. Soc.2024, 146 (11), 7649-7657. DOI: 10.1021/jacs.3c14045.
• Suating, P.; Ewe, M. B.; Kimberly, L. B.; Arman, H. D.; Wherritt, D. J.; Urbach, A. R. Peptide recognition by a synthetic receptor at subnanomolar concentrations. Chem. Sci. 2024, 15 (14), 5133-5142. DOI: 10.1039/d4sc01122h.
• Suating, P.; Ernst, N. E.; Alagbe, B. D.; Skinner, H. A.; Mague, J. T.; Ashbaugh, H. S.; Gibb, B. C. On the Nature of Guest Complexation in Water: Triggered Wetting-Water-Mediated Binding. J. Phys. Chem. B 2022, 126 (16), 3150-3160. DOI: 10.1021/acs.jpcb.2c00628.
• Suating, P.; Nguyen, T. T.; Ernst, N. E.; Wang, Y.; Jordan, J. H.; Gibb, C. L. D.; Ashbaugh, H. S.; Gibb, B. C. Proximal charge effects on guest binding to a non-polar pocket. Chem. Sci. 2020, 11 (14), 3656-3663. DOI: 10.1039/c9sc06268h.

• ​American Chemical Society
  
• Royal Society of Chemistry