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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Transannular rearrangement of activated 2,5-diketopiperazines: a key route to original scaffolds
Daniel Farran1, Isabelle Parrot, Loïc Toupet
1Institut des Biomolécules Max Mousseron, UMR CNRS 5247, Université Montpellier 1, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 5, France.
Abstract:
An efficient and original stereocontrolled transannular rearrangement starting from activated 2,5-diketopiperazines has been developed, an opportunity for the medicinal chemistry field, which requests access to novel biological scaffolds. This powerful ring contraction, which can be related to a stereoselective aza-version of the Chan rearrangement, allows for example the one-step synthesis of various tetramic acids, access to 2-disubstituted statins, or the synthesis of relevant lactam-constrained dipeptide mimetics using a TRAL-RCM sequence.
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