Eremophilane, Bakkane Fukinane , Ishwarane

Acid-catalysed rearrangement of 11,12-dihydroparadisiol (382) to 11,12-dihy-drovalencene (383) has provided further support for the 1,2-methyl shift postu- 

Reagents i, H202-NaOH-MeOH ii, Li-NH3 iii, (CH2SH)2-Bp3-HOAc iv, Raney Ni(W-2)-EtOH 

Experimental details for the previously reported synthesis of ( )-bakkenolide-A (411) (syn. fukinanolide) have been provided in a recent paper which also describes the potential of [2,3]sigmatropic rearrangement in natural product synthesis. In the particular case of bakkenolide-A the correct configuration at C-7 is achieved by [2,3]sigmatropic rearrangement of the intermediate (409) (cf. Vol. 5, p. 85). A 

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