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Peridinin is known as a representative auxiliary light harvesting pigment for photosynthesis in the sea. In the peridinin-chlorophyll (Chl) a-protein (PCP) complex, exceptionally high (>95%) energy transfer efficiencies from peridinin to Chl a has been reported. This energy transfer efficiency is thought to be related to the unique structure of peridinin, which possesses allene and ylidenbutenolide functions and the unusual C37 carbon skeleton referred to as a ‘nor-carotenoid’. There are, however, no studies on the subjects of why peridinin possesses a unique allene group and an irregular C37 skeleton, and how these functions play a role in the exceptionally high energy transfer. We have established the highly efficient synthesis of natural peridinin and successfully synthesized its allene and conjugated polyene modified derivatives. Measurements of their ultrafast time resolved spectra and Stark spectra have strongly suggested that these structural feature of peridinin has essentially contributed to its super ability of energy transfer.

As a demonstration for an easy supply of the enantiomerically pure intermediate for the synthesis of labdane diterpenoids, stereocontrolled synthesis of (+)-acuminolide was achieved, and its absolute configuration was determined.

The synthesis of a novel sphingosine kinase inhibitor, (−)-F-12509A ((−)-1), was achieved in a highly efficient manner that included nine longest linear steps and 45% overall yield from (−)-bicyclic β-ketoester (−)-2, and its absolute configuration was determined to be (5S,9S,10S).

A stereocontrolled, formal synthesis of a tetracyclic sesterterpene, (+)-scalarenedial, was achieved by means of repeating the same ring construction method and a simple resolution of the intermediary tetracyclic β-ketoester with a chiral auxiliary.