| Abstract
| - The 3-alkene-1,2,5-triol structure is not only a major framework of biologically important molecules butalso a new functional-group-rich unit for synthesis of polyols and sugars. A method furnishing such triolderivatives 8 was developed and successfully applied to synthesis of decarestrictine D (18). First, couplingreaction of the unprotected alcohols 2 with borates 4 was investigated to produce the dienyl alcohols 6with NiCl2(dppf) in Et2O/THF (5:1) at room temperature. The hydroxyl-group-directed epoxidation of 6followed by palladium-catalyzed reaction with AcOH (Scheme 1) furnished 3-alkene-1,2,5-triol derivatives8. Since each step proceeded with high stereo- and regioselectivities, the stereochemistry of 8 has beencorrelated with the olefin geometry of 6. With the above transformation in mind, synthesis of the fullcarbon skeleton of decarestrictine D (18) could be designed easily and was completed successfully.Furthermore, a new seco acid 19b with the MOM protective group for the three hydroxyl groups wasfound to afford macrolide 48 in a yield higher than those reported previously.
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