From termite soldier's secretions: The enantioselective total synthesis of the diterpene (+)‐cubitene is described. The route is characterized by the cyclization of a carvone‐derived C20 allylphosphate with SmI2, followed by fragmentation to the twelve‐membered ring. As a result, perfect stereocontrol of the isopropenyl‐substituted positions is achieved.

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The total synthesis of the marine natural product parazoanthine F from the sea anemone Parazoanthus axinellae is described. The key problem was the assembly of an N‐styrylhydantoin moiety. It was possible to cleanly hydroxylate the benzylic position of the corresponding phenethyl unit by treatment with cerium ammonium nitrate. However, elimination to the alkene proved to be surprisingly difficult. The breakthrough came after optimizing the CuI/N,N′‐dimethylethylenediamine‐mediated C–N coupling of a 2,2,4,6,7‐pentamethyl‐5‐sulfonyl‐dihydrobenzofuran‐protected arginine amide with p‐methoxystyryl bromide under microwave conditions (70 °C, 200 W) in the presence of Cs2CO3. Our studies culminated in a short approach with an overall yield of about 12 %.

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Cubitane: A Rare Diterpenoid Skeleton -[39 refs.]. -(WEFER, J.; SIMON, K.; LINDEL, T.; Phytochem. Rev. 12 (2013) 1, 95-105, http://dx.doi.org/10.1007/s11101-012-9257-1 ; Inst. Org. Chem., TU Braunschweig, D-38106 Braunschweig, Germany; Eng.) -Lindner 37-200