| Abstract
| - The enantioselective synthesis of the previously proposed structure of malyngamide U (1) wasaccomplished in 18 steps from (S)-(+)-carvone. The key steps involved a hydroxymethylation of (S)-(+)-carvone and an asymmetric Henry reaction of aldehyde (+)-5, as well as condensation with the acid3. The 1H and 13C NMR data of the synthetic compound 1 were not consistent with the data of thereported malyngamide U. The C-2‘ epimer of compound 1 was therefore synthesized by a similar reactionsequence. While the NMR data of C-2‘ epimer 23 were in full agreement with those of the reportedproduct, the discrepancy in the specific rotation data suggested the correct structure of malyngamide Ushould be structure 2, in which the absolute configuration of the amine part was enantiomeric with thatin compound 23. Then the correct absolute configuration of revised malyngamide U (2) was confirmedby the similar synthesis from (R)-(-)-carvone.
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