A novel bifunctional thiourea catalyzed formal [5 + 1] cycloaddition of oxindoles and ester-linked bisenones was successfully developed. This strategy involves two sequential Michael additions, leading to spirooxindole δ-lactones with three contiguous stereocenters including an all-carbon quaternary center with high diastereo- and enantioselectivites. In addition, a remarkable N-substituent effect was observed on the reactivity and selectivity.
No takes yet. Share an insight, caveat, or question.
Zhao et al. (2014) studied this question.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: