Synthesis of 7-substituted dehydronoraporphines, with some biogenetic considerations

Abstract N-protected 7-methyl-6a,7-dehydronoraporphines were synthesized by the intermolecular benzyne cycloaddition approach. During basic hydrolysis of the N-protecting group, oxidation of these compounds by oxygen led to guacoline and other 7-hydroxy-7-methyl-6,6a-dehydronoraporphines in what may be a biomimetic process.