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The first total syntheses of the Lycopodium alkaloids (+)-nankakurine A, (+)-nankakurine B and the originally supported structure of nankakurine A is feature a demanding intramolecular azomethine imine cycloaddition as the key step is reported. The reaction generated the octahydro-3,5-ethanoquinoline moiety and installed the correct relative configuration at the spiropiperidine ring juncture.

The first total synthesis of (+)-lycoflexine, a constituent of Lycopodium clavatum var. inflexum, is achieved in eight steps. The synthesis has included a tandem Sakurai/aldol sequence, a novel hydroboration/oxidation procedure, a deprotection/transannular Mannich reaction, and a tandem catalysis cascade combining an enyene ring-closing metathesis and a selective hydrogenation.

The total synthesis of (+)-fawcettimine is completed in a stereoselective manner starting from the oxatricyclo[7.3.0.[0.sup.1,5]]dodecanedione derivative. The construction of the azonane framework by the intramolecular Mitsunobu reaction is the crucial step in the total synthesis and also the total synthesis of (+)-lycoposerramine-B is achieved via the common synthetic intermediate.

The total synthesis of the Lycopodium alkaloid complanadine A, which is an unsymmetrical dimer of lycodine is achieved by using a common tetracyclic precursor. The development of a late-stage site-selective C-H functionalization of a pyridine moiety to arrive at a key boronic ester intermediate is the main factor for the success of the synthesis.

A highly efficient oxidative C-N bond forming reaction that relies on the union of a nitrogen anion and a carbon anion was developed to perform enantioselective total synthesis of architecturally complex Lycopodium alkaloid lyconadin A and related derivatives. The synthetic study evidence suggested that the mechanism of the C-N bond formation encompassed polar as well as radical processes.

A detailed study report on the enantioselective total syntheses of (+)-lyconadin A and (-)-lyconadin B is presented. The key steps to complete the synthesis include an aminoiodo olefin cyclization, in conjunction with [alpha]-pyridinone and 3,4-dihydropyridinone annulation protocols.

An unprecedented oxidative C-N bond-forming reaction was used to conduct total synthesis of lyconadin A. The results from the synthesis could help to gain insight into the biosynthetic relationships Lycopodium natural products and their related derivatives.