Grayanotoxins synthesis

The conversion of the relay (128) into grayanotoxin II has been described earlier. The synthesis of this relay has been achieved utilizing the photochemical rearrangement of the dienone (126) to the cyclopentanone (127). The conversion of... 

Samarium(II) iodide-promoted radical cydizations have also played a key role in the total synthesis of (-)-grayanotoxin III [43b]. Among the methods utilized for the synthesis of this molecule was an intramolecular ketyl olefin coupling reaction generating a bridged bicyclic ring system (Eq. 68). 

Naturally occurring and related compounds - The structure and synthesis of oudenone (XIX), the hypotensive mentioned last year, has now been reported.Acetyl andromedol (XX, grayanotoxin I), obtained from various species of Rhododendron, is hypotensive in cats at 0.0l mg/kg (l.v.) artefacts with related structures are also hypotensive in cats or rats. ... 

Shiozaki, M., Mori, K., Matsui, M., and Hiroka, T, Photochemical synthesis of compounds with grayanotoxin skeleton. Tetrahedron Lett., 657, 1972. 

Okuno, T., and T. Matsumoto Synthesis of a cw-Perhydroazulene Derivative Related to Grayanotoxin. Tetrahedron Letters 1969, 4077. 

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