Total syntheses of melodienones by redox isomerization of propargylic alcohols.

A remarkable base-promoted methodology for the rapid construction of the (E)- and (Z)-γ-oxo-α,β-alkenoic ester skeletons from readily accessible vinyl propargylic alcohols through modified redox isomerization was uncovered. This approach manifested its high simplicity and efficiency with excellent tolerance of functional substituents, which led to the straightforward structural modifications of various natural products and efficient total syntheses of melodienone, homomelodienone, isomelodienone, and homoisomelodienone within 4 linear steps.

Structural elucidation, total synthesis, and cytotoxic activity of effphenol A.

A highly substituted phenol derivative, effphenol A (1), was isolated from the deep-sea-derived fungus Trichobotrys effuse FS524. Its complete structural assignment was established through a combination of spectroscopic analysis together with single-crystal X-ray diffraction experiments and further unequivocally confirmed by a biomimetic total synthesis. Structurally, effphenol A possesses a poly-substituted 6-5/6/6 tetracyclic ring system, which represents the first case of such a skeleton found in nature.

The Biomimetic Total Syntheses of the Antiplasmodial Tomentosones A and B.

The first biomimetic total syntheses of natural phloroglucinols tomentosones A and B and their analogues have been accomplished. The synthetic strategy primarily referred to the potential biosynthetic precursors and their possible sequence of segments assembly by chemological evolution of the structural entities and enabled rapid access of the titled compounds in a practical fashion.

Triterpenoids with antiproliferative activities from the twigs and leaves of .

One new pentacyclic triterpenoid, urs-12,16-dien-3-one (), together with twelve known pentacyclic triterpenoids (), were isolated from the twigs and leaves of . Their structures were characterized by their 1D- and 2 D-NMR spectra analysis and mass spectra studies. Furthermore, all isolated compounds were tested the inhibitory effect on proliferation of six human cancer cell lines , including NCI-H441, NCI-H460, A549, SKOV3, hela, and caki-1 cells.

Two New Abietane Diterpenoids from Selaginella moellendorffii Hieron.

Two new abietane diterpenoids, (3S,5R,10S)-3-hydroxy-12-O-demethyl-11-deoxy-19(4→3)-abeo-cryptojaponol, 12,19-dihydroxyabieta-8,11,13-trien-7-one, were isolated from Selaginella moellendorffii Hieron., together with one known abietane diterpenoid and four known tetracyclic triterpenoids. Their structures were characterized by their 1D- and 2D-NMR, ECD and mass spectral studies.

Biomimetic Total Syntheses of Sanctis A-B with Structure Revision.

The first concise total syntheses of sanctis A and B were reported, and it enabled revision of the structure of sanctis B through single-crystal X-ray diffraction. The established synthetic approach mainly mimics a biosynthetic olefin isomerization/hemiacetalization/dehydration/[3 + 3]-type cycloaddition cascade sequence, offering a viable synthetic methodology to efficiently access sanctis A-B and their analogues.