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The first asymmetric synthesis of the previously unknown (-)-methyl palustramate is reported. The stereoselective synthesis featured a conformationally restricted Claisen rearrangement methodology to produce 1-benzylpipecolic ester as well as a new approach for debenzylation of 1-benzylpiperidines to successfully remove the benzyl protecting group, which traditional methods failed to accomplish. Research is being conducted on the usse of the methodology to the synthesis of (+)-palustrine.

The naturally occurring indolizidine alkaloid (-)-indolizidine 167B was prepared in nine steps with a 5.8% overall yield from an amino ester. This synthesis illustrates the importance of the Claisen rearrangement technique for the preparation of enantiopure indolizidine alkaloids from readily available alpha-amino acids. Moreover, the preparation of (-)-indolizidine 167B demonstrates the short pathway to N-benzylpipecolic esters.