Isostegane synthesis

Fig. 6 Synthesis of isostegane using hypervalent iodine reagent PIFA (taken from [39] by permission from Kluwer)...

Another clue for the biogenesis of steganes was given by the early work of Schlessinger and co-workers, who reported the biomimetic total synthesis of ( )-isostegane, Fig. (7) [84],... 

Fig. (22). Enantioselective synthesis of (-)-isostegane by Enders [125,126] (Ar1 = piperonyl, Ar2 = 3,4,5-trimethoxyphenyl)...

Fig. (7). Biomimetic synthesis of racemic isostegane [84] (TFA = trifluoroacetic acid)...

A short synthesis of ( )-isostegane, a tetracyclic dibenzocycloota-diene lactone, has been achieved by a sequential double a, -substitution of an electron-deficient ethylene derivative, in this case zl P-butenolide, followed by non-phenolic oxidative coupling with VOFg . An equally short synthesis of methyl jasmonate has been achieved through 1,4-addition-alkylation of cyclopentenone . 

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