Synthetic studies on polymaxenolides: model studies for constructing dihydropyran portion and synthesis of lower portion

With a goal of the total synthesis of polymaxenolide, the first hybrid marine natural product, the model studies for constructing the dihydropyran portion based on the originally proposed biosynthesis (C–C bond formation followed by dehydrative cyclization) and the synthesis of the lower portion (the C1–C3, C7–C17 portion) based on an iodide-induced Morita–Baylis–Hillman type reaction (a three-component assembly) followed by Suzuki–Miyaura cross-coupling are described.