| Abstract
| - Two efficient and stereoselective methods are described for the preparation of aryl and heteroarylceramide analogues 2 and 3. The first route involves the addition of an aryllithium or aheteroaryllithium reagent (7a or 25a, respectively) to the l-serine-derived aldehyde 4, followed byhydrolysis of the oxazolidine, liberation of the amino group, and N-acylation. The second route,which was used to prepare arylceramide analogue 2 in eight steps and 28% overall yield startingwith 3-bromobenzaldehyde, utilizes a Heck reaction to afford (E)-α,β-unsaturated ester 16, thenosmium-catalyzed asymmetric dihydroxylation for the introduction of the desired chirality at C-2and C-3. Regioselective α-azidation of α-O-nosyl-β-hydroxyester 18 with sodium azide, followed byLiAlH4 reduction of the azido and ester groups and N-acylation, complete the synthesis ofarylceramide analogue 2.
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