Asymmetric Synthesis of (-)-6-Desmethyl-Fluvirucinine A₁ via Conformationally-Controlled Diastereoselective Lactam-Ring Expansions.

The versatile synthesis of (-)-6-desmethyl-fluvirucinine A₁ was accomplished at a 24% overall yield through a thirteen-step process from a known vinylpiperidine. The key part involved the elaboration of the distal stereocenters and a macrolactam skeleton via conformationally-induced diastereocontrol and the iterative aza-Claisen rearrangements of lactam precursors.

Identification and Structural Analysis of New Nrf2 Activators by Mechanism-Based Chemical Transformation of 15-Deoxy-Δ -PGJ.

Mechanism-based chemical transformation of 15-deoxy-Δ -PGJ (15d-PGJ ) resulted in a series of new NF-E2-related factor-2 (Nrf2) activators and detailed elucidation of the function of each electrophilic binding site. In addition, HO-1 expression resulting from Nrf2 activation through enhanced dissociation of the Keap1-Nrf2 complex by the new activators was proved.

Concise and enantioselective total synthesis of 15-deoxy-Δ-(12,14)-prostaglandin J(2).

The concise and enantioselective synthesis of 15-deoxy-Δ(12,14)-prostaglandin J(2) (15d-PGJ(2)) has been accomplished in 11 steps from a known alcohol. The key step of the synthesis involves an asymmetric Rh-catalyzed cycloisomerization of ene-ynone, followed by an olefin isomerization.

A concise total synthesis of (+)-tetrabenazine and (+)-α-dihydrotetrabenazine.

Highly concise asymmetric total syntheses of (+)-tetrabenazine (1), a drug for the treatment of chorea associated with Huntington's disease, and of (+)-α-dihydrotetrabenazine (2), an active metabolite of 1, have been accomplished. Our synthetic route features a trans-selective enol etherification, followed by an unprecedented cation-dependent aza-Claisen rearrangement to establish the carbon framework and two stereogenic centers of tetrabenazine. The syntheses consist of seven steps (34 % overall yield) for (+)-2 and eight steps (22 % overall yield) for (+)-1.