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A Rh(II)-catalyzed oxy-alkynylation of acceptor-acceptor carbenes using EBX reagents was successfully developed. The key alkyne-transfer step is likely to occur through a tandem process involving a β-addition, an α-elimination, and a 1,2-shift, which was supported by the formation of alkylidene carbene. Various diverse C2-quaternary alkyne-substituted benzofuran-3-ones and 2,2,4,5-tetrasubstituted 3(2 H )-furanones can be synthesized smoothly, depending on the choice of diazo compounds and the base additives. Furthermore, this reaction is characterized by mild conditions, high functional group compatibility, and a broad substrate scope.

A cooperative Rh(II)/Pd(0) dual-catalysis strategy that promotes a cyclization/allylic alkylation cascade of stable α-diazo-δ-keto-esters has been developed. Highly substituted 3(2 H )-furanones with a C2-quaternary center can be obtained efficiently under mild conditions via one-pot synthesis. Remarkably, this binary catalytic system shows high chemo-, regio-, and stereoselectivity and excellent tolerance to various functionalities.

The first catalytic asymmetric total synthesis of (+)- and (-)-paeoveitol has been accomplished in 42% overall yield via a biomimetic hetero-Diels-Alder reaction. The chiral phosphoric acid catalyzed hetero-Diels-Alder reaction showed excellent diastereo- and enantioselectivity (>99:1 dr and 90% ee); two rings and three stereocenters were constructed in a single step to produce (-)-paeoveitol on a scale of 452 mg. This strategy enabled us to selectively synthesize both paeoveitol enantiomers from the same substrates by simply changing the enantiomer of the catalyst.

(+)-Paeoveitol and (-)-paeoveitol, a pair of new norditerpene enantiomers, were isolated from the root of Paeonia veitchii. Their structures and absolute configurations were determined on the basis of extensive analysis of 1D and 2D NMR spectra, crystal X-ray diffraction, and electronic circular dichroism (ECD). A possible biogenesis involving two molecules of paeoniflorin was postulated.

(±)-Sweriledugenin A, a pair of novel enantiomeric lactones, were isolated from Swertia leducii under the guidance of LC-MS investigation. The enantiomeric separation was achieved by HPLC on a chiral column. Their structures were determined by extensive NMR spectra, X-ray, and quantum calculations. (+)-Sweriledugenin A and (-)-sweriledugenin A showed activities inhibiting HBV DNA replication with the IC50 values of 36.86 and 26.55 μM on the HepG 2.2.15 cell line in vitro.