Synthesis of Nankakurines A and B via Luciduline

Significance

Nankakurine A, extracted from ­Lycopodium hamiltonii, induces the secretion of neurotrophic factors, promoting glial-cell-­mediated morphological differentiation. There is considerable interest in these molecules as diseases such as Alzheimer’s and Parkinson’s are ­associated with neurotrophic deficiency. Notable steps in this efficient synthesis include an intramolecular Mannich cyclization and a stereoselective imino allylation.