lycodine and decalin

A synthetic approach to complanadine alkaloids is described which employs a Kondrat'eva reaction to construct the pyridine rings. The viability of this approach is demonstrated by its application to a model substrate accessed from unfunctionalized decalin. The key transformation affords the desired tetracyclic architecture with unprecedented incorporation of substituents on the pyridine ring, implicating the oxazole α-hydroxy group as an active participant in the cycloadduct fragmentation process.

Topics: Alkaloids; Alkenes; Cycloaddition Reaction; Heterocyclic Compounds, 4 or More Rings; Molecular Structure; Naphthalenes; Oxazoles; Pyridines