A new spirocyclic proline-based lactam as efficient type II′ β-turn inducing peptidomimetic

Modular, One-Pot, Sequential Aziridine Ring Opening-S(N)Ar Strategy to 7-, 10-, and 11-Membered Benzo-Fused Sultams

The generation of common and stereochemically rich medium-sized benzo-fused sultams via complementary pairing of heretofore-unknown (o-fluoroaryl)sulfonyl aziridine building blocks with an array of amino alcohols/amines in a modular one-pot, sequential protocol using an aziridine ring opening and intramolecular nucleophilic aromatic substitution is reported. The strategy employs a variety of amino alcohols/amines and proceeds with 6 + 4/6 + 5 and 6 + 1 cycloetherification pathways in a highly chemo- and regioselective fashion to obtain skeletally and structurally diverse, polycyclic, 10- to 11- and 7-membered benzo-fused sultams for broad-scale screening.

Tetrahydro-β-carboline-based spirocyclic lactam as type II' β-turn: application to the synthesis and biological evaluation of somatostatine mimetics

The synthesis of novel spirocyclic lactams, embodying D-tryptophan (Trp) amino acid as the central core and acting as peptidomimetics, is presented. It relies on the strategic combination of Seebach's self-reproduction of chirality chemistry and Pictet-Spengler condensation as key steps. Investigation of the conformational behavior by molecular modeling, X-ray crystallography, and NMR and IR spectroscopies suggests very stable and highly predictable type II' β-turn conformations for all compounds. Relying on this feature, we also pursued their application to two potential mimetics of the hormone somatostatin, a pharmaceutically relevant natural peptide, which contains a Trp-based type II' β-turn pharmacophore.