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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
Toward the total synthesis of haliclonin A: construction of a tricyclic substructure
Shi-Peng Luo1, Lian-Dong Guo, Long-Hui Gao
1Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, PR China.
Abstract:
Three keys to success: A concise method for the construction of a tricyclic substructure (2) of haliclonin A (1) in racemic form is described (see figure). This synthesis features a new Pd-mediated chemoselective carbonyl-enone coupling reaction, an organocatalytic reaction, and a ring-closing metathesis reaction for the construction of the macrocyclic ring as key steps.
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