Total Synthesis of (±)-Spiroaxillarone A via a Reversible Sulfa-Michael Addition

Asymmetric total synthesis of penicilfuranone A through an NHC-catalyzed umpolung strategy

The first asymmetric total synthesis of penicifuranone A was accomplished in eight steps through an NHC-catalyzed umpolung strategy. Key features of the synthesis include an Al-Salen catalyzed asymmetric cyanosilylation to install the tertiary alcohol of gregatin A, and an NHC catalyzed Stetter-Aldol cascade reaction. The umpolung strategy of the benzyl aldehyde fragment facilitated a convergent formal [4 + 2] annulation with gregatin A, ultimately leading to the formation of penicifuranone A.

Bioinspired Synthesis of Microstegiol and Biosynthetically Related Skeleton-Rearranged Abietanes

We report a bioinspired synthesis of microstegiol and biosynthetically related skeleton-rearranged abietane diterpenoids from commercially available carnosic acid. The strategy features a Wagner-Meerwein type methyl migration followed by several cascade transformations, enabling the divergent synthesis of five abietane diterpenoids, including viridoquinone, prattinin A, saprorthoquinone, microstegiol, and 1-deoxyviroxocin.

The Michael donor-acceptor reactivity of curcumins in the synthesis of diverse multi-functional scaffolds

Curcumin is a key constituent of turmeric with a variety of biological activities. From a chemical point of view, curcumin contains different functional groups that can undergo multiple transformations such as Michael addition, cycloaddition, click reaction, polymerisation, etc. Among these, Michael-type reactions under benign conditions constitute a captivating domain of curcumin's reactivity. To the best of our knowledge, no review focusing on the Michael donor-acceptor reactivity of curcumins has been published to date. Herein, we have compiled the chemistry of curcumins with respect to their chemical synthesis, biosynthesis, and involvement in chemical transformations, especially in Michael additions with advances in mechanistic aspects and understanding.

Recent Advances in Organocatalyzed Asymmetric sulfa-Michael Addition Triggered Cascade Reactions

The sulfa-Michael addition reaction is a crucial subset of the Michael addition reaction, and aroused the interest of numerous synthetic biologists and chemists. In particular, sulfa-Michael addition triggered cascade reaction has developed quickly in recent years because it offers an efficient method to construct C-S bonds and other bonds in one approach, which is widely applicable for building chiral pharmaceuticals, their intermediates, and natural compounds. This review emphasizes the recent advancements in sulfa-Michael addition-triggered cascade reactions for the stereoselective synthesis of sulfur-containing compounds, including sulfa-Michael/aldol, sulfa-Michael/Henry, sulfa-Michael/Michael, sulfa-Michael/Mannich and some sulfa-Michael triggered multi-step processes. Moreover, some reaction mechanisms and derivatization experiments are introduced appropriately.