Tauropinnaic acid from Pinna muricata

Three novel related marine alkaloids, halichlorine (1148) from the sponge Halichondria okadai (1177, 1178) and pinnaic acid (1149) and tauropinnaic acid (1150) from the bivalve Pinna muricata (1179), have been the objects of much synthetic interest in view of their pronounced biological activity (inhibition of the vascular cell adhesion molecule-1) (1180). Synthesis of these alkaloids led to both revision and confirmation of the original structures (1181,1182). The syntheses of the previously known chlorine-containing cylindricines have been reviewed (1183). 

Chou T, Kuramoto M, Otani Y, Shikano M, Yazawa K, Uemura D (1996) Pinnaic Acid and Tauropinnaic Acid Two Novel Fatty Acids Composing a 6-Azaspiro[4.5]decane Unit from the Okinawan Bivalve Pinna muricata. Tetrahedron Lett 37 3871... 

Tong, C., Kuramoto, M., Otani, Y, Shikano, M., Yazawa, K. and Uemura, D, 1996. Pinnaic acid and tauropinnaic acid two novel fatty acids composing a 6-azaspiro[4.5]decane unit from the Okinawan bivalve Pinna muricata.. Tetrahedron Lett 37, 3871-3874. 

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