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The L-acid (C1-C18) fragment of pamamycin-593 and de-Nmethylpamamycin-579, strong aerial mycelium-inducers of Streptomyces alboniger, was synthesized using a cis-selective iodoetherification and a nucleophilic addition of a cerium acetylide to an aldehyde as the key steps.

An improved asymmetric synthesis of renin inhibitor DS-8108b (1) is described. This compound consists of three intermediates: 4-aminoadamantan-1-ol, ketopiperazine, and chiral lactone which contains three stereogenic centers. Especially, the chiral lactone is a key intermediate, and development of a scalable synthetic method was required, considering the quality, speed, and manufacturing cost. We established a scalable synthetic method of 1 from 4,6-O-benzylidene-d-glucose for early clinical studies. Furthermore, a highly efficient synthetic route of the chiral lactone for manufacturing was also successfully developed from n-butyryl chloride via Evans stereoselective alkylation, followed by stereoselective bromolactonization. In addition, a unique and highly efficient conversion protocol was developed from α-bromo-N-(2-nitrobenzenesulfonyl)amide to apparent rearranged diamine derivatives with a sequential aziridination–substitution reaction in one-pot.

Four stereoisomers of (þ)-pteroenone, a defensive metabolite of the abducted Antarctic pteropod Clione antarctica, were synthesized by employing anti-/syn-selective aldol reactions as the key step. These compounds displayed no antifeedant activity against a generally benthic Antarctic fish that does not cooccur with this pteropod.

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