Formal Synthesis of Lobatamides A and C
Yuki Nakahara1, Takumi Fukuda1, Ryo Fujii1
1School of Pharmaceutical Sciences, University of Shizuoka, 52-1 Yada Suruga-ku, Shizuoka 422-8526, Japan.
Abstract:
Lobatamides, featuring a unique 15-membered dilactone core, are a family of marine natural products isolated from the tunicate Aplidium lobatum and exhibit inhibitory activity against mammalian vacuolar-type proton pump ATPase (V-ATPase). Herein, we report an alternative route to Sato's intermediate, achieving formal syntheses of lobatamides A and C. Key steps include the palladium-catalyzed Suzuki-Miyaura coupling reaction to give a salicylic acid derivative containing a trisubstituted (Z)-olefin and the Nozaki-Hiyama-Takai-Kishi (NHTK) reaction to construct the 15-membered dilactone core.
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