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Cyclopenta[d]isoxazoline β-Turn Mimics: Synthetic Approach, Turn Driving Force, Scope, and Limitations.

ABSTRACT: Model β-turn inducers were prepared from constrained oxazanorbornene aminols. Taking advantage of the starting materials geometry, new diastereoisomeric compounds were synthesized, introducing different amino acidic residues. The products were spectroscopically characterized (VT and NMR titration). Temperature coefficients in dimethyl sulfoxide denote the existence of an intramolecular hydrogen bond. Chiroptical properties disclosed a β-turn arrangement of the synthesized compounds. The fused isoxazoline ring constraints the cyclopentane moiety, stabilizing a boatlike conformation that ensures the turn efficiency but limiting the accessibility to hindered amino acids.

SUBMITTER: Memeo MG

PROVIDER: S-EPMC6645019 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Cyclopenta[<i>d</i>]isoxazoline β-Turn Mimics: Synthetic Approach, Turn Driving Force, Scope, and Limitations.

Memeo Misal Giuseppe MG Bruschi Marco M Bergonzi Luca L Desimoni Giovanni G Faita Giuseppe G Quadrelli Paolo P

ACS omega 20181018 10

Model β-turn inducers were prepared from constrained oxazanorbornene aminols. Taking advantage of the starting materials geometry, new diastereoisomeric compounds were synthesized, introducing different amino acidic residues. The products were spectroscopically characterized (VT and NMR titration). Temperature coefficients in dimethyl sulfoxide denote the existence of an intramolecular hydrogen bond. Chiroptical properties disclosed a β-turn arrangement of the synthesized compounds. The fused is ...[more]

PMID: 31458062

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