Halichlorine, azaspirocycles

The molecular complexities of these architecturally novel alkaloids have prompted intense studies to elaborate new and efficient methods and strategies for the synthesis of these products. Hence, several stereocontrol approaches have been developed to successfully construct the azaspirocyclic core of pinnaic acids and halichlorine, providing access to the formal total synthesis and highly stereoselectivity of these molecules (Christie et al. 2004 Zhang et al. 2005 Andrade and Martin 2005 Clive et al. 2005 and references cited therein). In particular, Danishefsky s research group has reported the first total synthesis of halichlorine (Trauner et al. 1999), supporting the previous conclusions regarding the structure of this alkaloid (Kuramoto et al. 1996 Arimoto et al. 1998), and has... 

Zhang, H.L., Zhao, G., Ding, Y, and Wu, B. 2005. An efficient and enantioselective approach to the azaspirocyclic core of alkaloids formal synthesis of halichlorine and pinnaic acid. J Org Chem 70, 4954-4961. 

Pinnaic Acids and Halichlorine, Novel Marine Azaspirocycles. 167... 

Hurley PB, Dake GR (2008) Synthetic studies toward halichlorine complex azaspirocycle formation with use of an nbs-promoted semipinacol reaction. J Org Chem 73 4131—4138... 

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