In the course of our research for biologically active constituents from coniferous plants, a chromone derivative (1) and an abietane derivative (2) were isolated along with several diterpenes from Chamaecyparis pisifera. Structures of the new compounds were determined to be 5,7-dihydroxy-2-(1-acetyl-2-methoxycarbonylethyl)-chromone and rel-(8R,10R,20S)-8,10,20-trihydroxy-9(10→20)-abeo-abieta-9,13-dien-12-one by means of spectral methods including two-dimensional NMR experiments. Some of these abietane-type compounds isolated from this plants showed antibacterial activity against the gram-positive bacteria Staphylococcus aureus and Bacillus subtilis.

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The asymmetric Diels–Alder reaction of α,β-unsaturated aldehydes with cyclopentadiene is catalyzed by a novel chiral boron reagent generated in situ from boron tribromide and a chiral prolinol derivative, to afford the corresponding adducts in good yields with fairly good to excellent ees.

A unique catalyst, Au core and Pd shell bimetallic nanoparticles immobilized on porous silica exhibiting a considerable high activity for the hydrogenation of cyclohexene, was prepared via two steps composed of the sonochemical reduction method and the sol–gel process under a low temperature condition.

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