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Updated: Aug 14, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Stereoselective Sequence toward Biologically Active Fused Alkylidenecyclobutanes
Andreas N Baumann1, Michael Eisold1, Dorian Didier1
1Department of Chemistry and Pharmacy, Ludwig-Maximilians-University , Butenandtstraße 5-13, 81377 Munich, Germany.
Abstract:
Combining an efficient preparation of cyclobutenylmetal species, high-yielding cross-coupling reactions, and highly diastereoselective [4 + 2]-cycloaddition led to opening a new route toward the synthesis of fused alkylidenecyclobutanes containing up to five consecutive stereocenters. New complex architectures, analogues to protoilludane skeletons, were obtained in a very efficient manner and with a minimum number of steps starting from commercial sources and were tested for their cytotoxicity against leukemia cell lines HL60.
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