| Abstract
| - A program directed toward an asymmetric synthesis of pestalotiopsin A is described. The routing beginswith the dextrorotatory cyclobutanol 37, which is combined with the enantiomerically defined buildingblocks ent-15 and 16. These units are incorporated via stereocontrolled 1,2-nucleophilic addition andanti-aldol coupling, respectively. With these straightforward reactions accomplished, the sequel involvedthe introduction of terminal double bonds in anticipation of the fact that the (E)-cyclononene substructurecould be realized by ring-closing metathesis. This central issue was evaluated with several diene substratesand catalysts, all to no avail. Cross-metathesis experiments involving 59 and 65 with the functionalizedheptene 60 revealed a marked difference in the inability to engage interaction with the ruthenium catalyst.This awkwardness could not be skirted.
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