Asymmetric Synthesis of Functionalized α-Amino Acid Derivatives via the γ-Pyrone Carbaldimine-Based Organocatalytic
Maxim V Smirnov1,2, Madina Zhanabaeva1,3, Alexander S Kucherenko1
1N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninsky Prospect, 47, Moscow 119991, Russian Federation.
Abstract:
A powerful synthetic strategy for the asymmetric synthesis of enantiomerically enriched γ-functionalized α-amino acid derivatives based on the highly stereoselective proline-catalyzed Mannich-type reaction of pre-prepared or in situ-generated γ-pyrone-derived aldimines with carbonyl compounds and subsequent transformations of multifunctional reaction products has been developed. A significant positive nonlinear effect was detected for the key organocatalytic reaction. The developed strategy was applied for facile gram-scale preparation of (S)-γ-oxonorvaline, used for site-specific modification of proteins, and both enantiomers of amycolatolide A recently isolated from the lichen-derived actinomycete Amycolatopsis sp. YIM 130923.
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