(±)-耳壳藻内酯的全合成研究(Ⅱ)

Total Synthesis of (±)Caulilide(Ⅱ)

以2,6,6-三甲基环己-2-烯-1,4-二酮为原料,经选择性羰基保护、W ittig反应、脱保护基、腈基水解和还原等5步反应合成了目标化合物,总产率可达6.0%.

The Caulilide which shows a potent cytotoxicity was synthesized from 2,6,6-trimethylcyclohex-2- ene-1,4-dione via selective ketalization, Wittig reaction, deprotection, hydrolysis-lactonization and reduction in 6. 0% total yield, in which wittig reaction was the key step. The difficulty of this reaction came from the strong blocking effect, many reaction conditions were optimized, a better yield of this reaction was gained in 57. 8%. The synthesis of caulilide was completed by reduction of a lactone with NaBH4 , the crude product was separated by high performance liquid chromatography to give the target compound.