Direct catalytic asymmetric Michael addition reactions of ketones to nitroolefins using newly developed chiral pyrrolidine-pyridine conjugate bases as catalysts are described. The desired 1,4-adducts are obtained in excellent yields with high enantio- and diastereoselectivities.

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Total synthesis of (-)-agelastatin A has been achieved starting from l-arabitol. The highlights in our synthesis include the preparation of vicinal diamine moiety by [3.3] sigmatropic rearrangement of allyl cyanate and construction of central ring-C with ring-closing metathesis.

The reaction of epoxides with nitrogen heterocycles such as indoles, pyrroles, imidazoles, and pyrazoles was studied under both high-pressure and silica gel-catalyzed conditions. Whereas it has been reported that the treatment of indole with styrene oxide at 10 kbar and 42 °C for 24 h gave 2-(3-indolyl)-2-phenylethanol in 56% yield, the same compound was obtained in 88% yield when the reaction was conducted on silica gel at rt for 1 week. Similarly, efficient reaction of epoxides with pyrroles, imidazoles, and pyrazoles was achieved. In terms of stereochemical features, the epoxide ring opening reaction of (R)-(+)-styrene oxide with indole was found to proceed stereoselectively in an SN2 fashion at the benzyl carbon, in either case.

Two new condensed guaiazulenoid pigments, gorgiabisazulene and gorgiagallylazulene, have been isolated from a gorgonian Acalycigorgia sp. and their structures have been established on the basis of spectroscopic and chemical evidence.

A new method for chiral diamine-catalyzed Robinson-type annulation was developed to construct cyclohexenone derivatives bearing a quaternary carbon stereogenic center at the 4-position in high enantiomeric excess. This method was successfully applied to the short synthesis of (+)-sporochnol A.

Four new bioactive polyacetylenes have been isolated from the marine sponge Petrosia sp. Their structures including absolute stereochemistry have been elucidated by spectral and chemical methods.

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