アレンのエンド型閉環反応を基盤とするlauthisan類の合成研究

抄録

A reliable and efficient procedure for constructing five- to eight-membered oxacycles has been developed. Treatment of allenes possessing sulfonyl group and a suitable hydroxyalkyl side chain at the C₁-position with potassium tert-butoxide in tert-butanol effected an endo mode ring-closing reaction at the sp-hybridized carbon center of allenyl moiety. On the basis of this developed endo mode ring-closing reaction, synthesis of 1,8-disubstituted oxocane and its highly oxygenated derivative were accomplished. Studies on the total synthesis of laurencin and related natural products isolated from red algae are now in progress.

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