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A highly enantio- and regioselective hydrosulfonylation of 1,3-dienes with sulfonyl hydrazides has been realized by using a palladium catalyst containing a monodentate chiral spiro phosphoramidite ligand. The reaction provided an efficient approach to synthetically useful chiral allylic sulfones. Mechanistic studies suggest that the reaction proceeds through the formation of an allyl hydrazine intermediate and subsequent rearrangement to the chiral allylic sulfone product. The transformation of the allyl hydrazine intermediate to the product is the enantioselectivity-determining step.

A supramolecular polymer was constructed from a light-driven overcrowded alkene switch modified with two alkylated gallic acid amide pendants (MSP-1). Upon UV irradiation, stable MSP-1 isomerized into unstable MSP-2, which induced the effective collapse of well-defined cross-linked supramolecular polymers, and the reassembly can be realized by aging at low temperature.

Total synthesis of (±)-Lingzhilactone B has been achieved for the first time in 13 steps. The key step features a semipinacol rearrangement to construct 5/5 bicyclic ring with adjacent quaternary carbon.

A novel and efficient trifluoromethanesulfonic acid-catalyzed sp(3)-sp(2) C-C bond formation reaction through the direct coupling of alcohols with alkenes has been realized under mild conditions. The present protocol provides an attractive approach to a diverse range of polysubstituted olefins in good to excellent yields with high stereo- and regioselectivities.

Two new C(30)-epimeric polycyclic polyprenylated acylphloroglucinols (PPAPs), named uralodins B and C (1 and 2, resp.), were isolated from the aerial parts of Hypericum henryi subsp. uraloides together with two new chromone glucosides, urachromones A and B (3 and 4, resp.), as well as 16 known compounds. Their structures were established by extensive NMR techniques and MS analysis. The epimers 1 and 2 always behaved like a single compound when examined by TLC, and were separated by HPLC. Their configuration was distinguished by comparative analysis of the NMR data with known analogues together with the ROESY experiment. All the isolated PPAPs were evaluated for their cytotoxic activities against HepG2, SGC7901, HL-60, and K562 cell lines. Compound 1 showed modest cytotoxic activities against SGC7901 and HL-60 cell lines, and 2 showed modest cytotoxic activities against HepG2, SGC7901, HL-60, and K562 cell lines.

Concise synthesis of (±)-Lingzhiol has been achieved. The key reaction involves one-step construction of a 5/5/6/6 tetra-ring backbone of Lingzhiol via epoxy-arene cyclization.

Spirocurcasone (II) and pyracurcasone (III) are prepared stereospecifically in one step from available curcusone.

Reaction of secondary alcohols with alkynes under optimized conditions A) produces E/Z-isomeric mixtures of the synthetically important structural motifs with the (E) isomer always predominating.

The reaction allows a new and efficient access to a number of di-, tri-, and tetrasubstituted olefins and proceeds with high regio- and stereoselectivity.

Isolation, structure determination and cytotoxicity of two new oleanane triterpenoids (I), (II), one new vibsane-type diterpenoid (III) and seven known compounds are described.

isolation, structure and cytotoxicity of brainicin (I), an unusual flavanol coupled with phenylpropyl and shikimic acid units, and new flavonol acylglycoside brainoside B (II) along with 14 known phenolic compounds

The 70% aqueous acetone extract of the aerial part of Viburnum foetidum var.foedidum afforded four new lignans (1-4) together with six known ones. The structures of the four new compounds were elucidated on the basis of I D (dimensional), 2D-NMR, and mass spectral analysis. The structure of compound 1, with a novel spirocyclic moiety, was also confirmed by X-ray diffraction analysis. Compounds 1-10 were evaluated for their cytotoxic activity. However, none of the compounds showed significant cytotoxic activity.

Two new sesquiterpene glucosides onitioside A (1) and dennstoside B (2), were isolated from the 95% EtOH extract of Dennstaedtia scabra (WALL.) MOORE, together with seven known compounds, onitisin (3), pterosin A (4), pinocembrin (5), pinocembrin 7-rutinoside (6), kaempferol (7), nicotiflorin (8), and galangin (9). Their structures were determined by extensive spectroscopic analysis.