Intramolecular carbenoid-carbonyl cyclization sequence

2 Application of the Method Toward Complex Tetrahydrofuranyl Natural Products 

The rhodium(II)-induced tandem cyclization-cycloaddition process has also been applied with notable success to the core structure of zaragozic acid by the Merck research group 94TL9185 . Zaragozic acid A (20) was discovered as a metabolite from an unidentified 

Further studies by the Hodgson group are still in progress with the fully oxygenated 6,7-dioxy core of zaragozic acid. 

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