Structural Determination of Montanacin D by Total Synthesis
摘要:
The first total syntheses of acetogenin 3 and its 4S,8R-isomer are described. The key step involves intermolecular metathesis of an alpha,beta-unsaturated ketone carrying a tetra hydropyranyl lactone with a tetrahydrofuran derivative. Compound 3 has spectroscopic and physical data consistent with those of natural montanacin D, suggesting that the absolute configuration of the natural product is as shown in 3.
Structural Determination of Montanacin D by Total Synthesis
摘要:
The first total syntheses of acetogenin 3 and its 4S,8R-isomer are described. The key step involves intermolecular metathesis of an alpha,beta-unsaturated ketone carrying a tetra hydropyranyl lactone with a tetrahydrofuran derivative. Compound 3 has spectroscopic and physical data consistent with those of natural montanacin D, suggesting that the absolute configuration of the natural product is as shown in 3.
Goniodenin is a lipophilic polyketide originating from plant sources and which possesses a potent cytotoxic activity against cancer cell lines. The first total synthesis of (+)-goniodenin has been achieved in 23 steps from (R)-glycidol. The synthetic sequence featured a cross metathesis for the formation of the C-8-C-9 bond and installation of the terminal gamma-butenolactone ring unit by the allcylation of alpha-phenylthio-gamma-butyrolactone with the corresponding C-3-O-triflate. The stereogenic center at C-18 carbon was created by Hiyama Fujita reduction of the corresponding ketone with high diastereoselectivity.