Addition of hydroxylamine to substituted 4-chlorobutanals gives intermediate nitrones that undergo tandem cyclization and then intramolecular dipolar cycloaddition to give the core ring system of the yuzurimine-type natural products. Ring-opening of the isoxazolidines gives amino alcohols that can be converted to 1, 3-oxazines, representing the tetracyclic core of alkaloids such as daphcalycic acid and daphcalycine.
[Miller, John F.; Furfine, Eric S.; Hanlon, Mary H.; Hazen, Richard J.; Ray, John A.; Robinson, Laurence; Samano, Vicente; Spaltenstein, Andrew Bioorganic and Medicinal Chemistry Letters, 2004 , vol. 14, # 4 p. 959 - 963]
