Design, Synthesis, and Conformational Analysis of Proposed β-Turn Mimics from Isoxazoline-Cyclopentane Aminols
Misal Giuseppe Memeo1, Mariella Mella1, Valentina Montagna1
1Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 - Pavia (Italy).
Abstract:
Constrained aminols from oxazanorbornene derivatives have the geometrical features to be used as β-turn inducers. Four different stereoisomers were prepared and spectroscopically characterized (MD calculations, NMR-titration and VT-NMR experiments). Temperature coefficients in DMSO are indicative for the existence of an intramolecular hydrogen bond. Chirooptical properties revealed a β-turn arrangement of all the synthesized compounds, where, depending on the absolute configuration of the cyclopentane spacer, they can be labeled as left- or right-handed turns.
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