N‑Heterocyclic Carbene-Catalyzed Atom-Economical and Enantioselective Construction of the C–S Bond: Asymmetric Synthesis of Functionalized Thiochromans

An N-heterocyclic carbene-catalyzed cleavage and recombination of the C–S bond was developed. This is an efficient example of NHC reacting with an unsaturated thioester to generate an α,β-unsaturated acyl azolium with high atom economy. This protocol affords an alternative route for the construction of highly functionalized thiochroman derivatives with three consecutive stereogenic centers with good to high yields, as well as excellent diastereoselectivity and enantioselectivity

Two new chemical constituents from the aerial parts of <i>Tripterygium wilfordii</i>

Tripterygium wilfordii has been historically employed as a conventional botanical insecticide and a plant of medicinal significance. A new dihydroagarofuran sesquiterpene (1) and a new acyclic compound (2), along with seven known compounds (3–9), have been isolated from the aerial parts of Tripterygium wilfordii. The identification of the structures of novel compounds were accomplished through comprehensive spectroscopic analyses, encompassing HRESIMS, NMR, UV, IR, and a comparative analysis with spectroscopic data from compounds previously characterised. In in-vitro bioassay, compound 8 exhibited significant inhibitory activity for NO release in LPS-induced RAW 264.7 cells, with an IC50 value of 15.7 μM.</p