• YAKHAK HOEJI
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• v.34 no.3
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• pp.166-170
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• 1990

An efficient synthetic route to macrolide is described. Eight-membered lactone was synthesized via palladium catalyzed intramolecular alkylation of allylic carbonate in high yield.

• YAKHAK HOEJI
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• v.39 no.1
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• pp.31-35
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• 1995

An unusual 10-membered lactone possesing ring-olefin at 7, 8-position has been efficiently synthesized. The $\omega$-hydroxy acid as a cyclization precusor was derived from $\varepsilon$-caprolactone in 41% overall yield of 7 steps and efficiently cyclized by Mukaiyama procedure.

• Journal of the Korean Chemical Society
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• v.39 no.2
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• pp.103-110
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• 1995

Phenylthio substituted 14-membered lactone(23) which can serve as a precursor of a potential antitumor antibiotics (6), was successfully prepared. The synthesis of the lactone was accomplished via lactonization of the corresponding enediyne hydroxy acid (22). This hydroxy acid was derived from Pd(0)-catalyzed coupling reaction of methyl pentynoate and cis-1,2-dichloroethylene followed by another Pd(0)-catalyzed coupling reaction of the resulting methyl chloroenyne ester (20) and enyneol (17). The required enyne alcohol was successfully synthesized from vinyltin compound (12) in good overall yield.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.188-190
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• 1998

Penicillide, having a 5H, 7H-dibenzo［b,g］［1,5］ dioxocin-5-one skeleton, was isolated from the culture broth of Penicillium sp. F60760 as a nonpeptide inhibitor of calpain, a calcium-activated papain-like protease. The $IC_50$ value for the effect of penicillide against m-calpaln was $7.1{\mu}M$. However, penicillide did not inhibit papain at a concentration of $200{\mu}M$. These results suggest that penicillide is a new class of nonpeptide calpain inhibitor having an eight membered lactone ring.