Pyrenophorin synthesis

When one looks further at how structures with a 7,4-relationship of heteroatoms may be accessed, one should consider either the sequence of a Claisen ester rearrangement followed by Wacker oxidation, or the iodolac-tonization or direct [66] lactonization reaction of the carbon-carbon double bond (Scheme 2.43). For an application in the context of pyrenophorin synthesis, see reference [67]. Note that in the course of this sequence the heteroatom, which was at C-1 of the allyUc alcohol, is moved over to C-2. 

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