Radical cyclization of β-alkoxyacrylates: Stereoselective synthesis of (−)-trans-Kumausyne

Efficient Synthesis of (−)-trans-Kumausyne via Tandem Intramolecular Alkoxycarbonylation−Lactonization

“…In summary, we have achieved an exceptionally concise and efficient synthesis of (−)- trans- kumausyne from dimethyl ( R )-malate (13 steps, 6.2% overall yield), which demonstrates the serviceability of the general plan outlined in Scheme for stereocontrolled construction of 3-oxygenated 2,5-dialkyltetrahydrofurans. In addition, this work serves to highlight the intrinsic power of tandem intramolecular alkoxycarbonylation−lactonization for building complexity rapidly, in atom-economical fashion.…”

Advances in Total Synthesis of Some 2,3,5‐Trisubstituted Tetrahydrofuran Natural Products

“…In 1997, Lee and co-workers [25] disclosed a stereoselective route to the synthesis of (À )-trans-kumausyne via a clever radical cyclization of β-alkoxyacrylates (Scheme 4). The synthesis began with the dithioacetal 33 b that was prepared from readily available D-(+)-xylose 33 a in four steps.…”

Progress in the Chemistry of Organic Natural Products 102

“…However, their strong toxicity restricts their commercial development as they severely affect the survival rate of B. amphitrite nauplii [81,904]. In another study from the same group, obtusol (28), caespitane (333), and caespitol (337) showed low levels of antialgal activity (C. fusca), while isoobtusol acetate (49), elatol (59), 135, puertitol B acetate (312), 8-acetylcaespitol (338), caespitenone (349), furocaespitane (352), laucapyranoid A (372), isopinnatol B (553) and dactylomelol (600), and dactylopyranoid (631) were inactive [50]. 3-epi-Perforenone A (379), 381 and 4-hydroxy-1,8-epi-isotenerone (397) were devoid of any activity against the alga C. fusca [399].…”