2 research outputs found
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