Cobalt versus Osmium: Control of Both trans and cis Selectivity in Construction of the EFG Rings of Pectenotoxin 4: ACIE 2017

Cobalt versus Osmium: Control of Both trans and cisSelectivity in Construction of the EFG Rings of Pectenotoxin 4

Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt- or osmium-based) allowed for the formation of THF rings with either trans or cis stereoselectivity. Fragment union using a modified Julia reaction then enabled the synthesis of an advanced synthetic intermediate containing the EF and G rings of the target.

Total Synthesis of (+)-Pochonin D and (+)-Monocillin II via Chemo- and Regioselective Intramolecular Nitrile Oxide Cycloaddition : Organic Letters 2017

Total Synthesis of (+)-Pochonin D and (+)-Monocillin II via Chemo- and Regioselective Intramolecular Nitrile Oxide Cycloaddition

Asymmetric total syntheses of (+)-pochonin D (1) and (+)-monocillin II (2), Hsp90 inhibitors with potent anticancer activity, have been accomplished where the macrolactone 3 was constructed through a chemo- and regioselective intramolecular nitrile oxide cycloaddition of diene 4.

Total Synthesis of Biselide E, a Marine Polyketide: Organic Letters 2017

Total Synthesis of Biselide E, a Marine Polyketide

The total synthesis of biselide E, a marine polyketide isolated from the Okinawan ascidian, has been accomplished. The highlight of this approach is the use of the β-elimination reaction of the chloroacetoxy group for the construction of an unstable six-membered α,β,γ,δ-unsaturated lactone portion at the late stage of the total synthesis.