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Updated: May 17, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Core scaffold-inspired stereoselective synthesis of spiropyrazolones via an organocatalytic Michael/cyclization
Luping Liu1, Yuan Zhong, Panpan Zhang
1Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences, Institute of Biochemistry and Molecular Biology, Lanzhou University, Lanzhou, China 730000.
Abstract:
Herein, the organocatalytic asymmetric Michael/cyclization sequence of α-isothiocyanato imides and esters with a variety of unsaturated pyrazolones is presented, in general, affording functionalized spiropyrazolones containing three contiguous stereogenic centers in high levels of diastereo- and enantioselectivity (up to 20:1 dr and 99% ee). Moreover, the current protocol provides a highly efficient and convenient strategy that allows rapid enantioselective construction of diversely spiropyrazolone skeletons with high optical purity.
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