The Biosynthetic Pathways as an Inspiration for Synthetic Challenges

The mutasynthon B replaces the missing natural intermediate B and is incorporated in the product 

SCHEME 1.9 (a) Biosynthetic pathway of wUd-type metabolites (b) precursor-directed biosynthesis the modified synthon B replaces the natural synthon B (c) biosynthetic pathway blocked by a mutation (the enzyme E4 is not functional) (d) mutasynthesis a mutasynthon B is introduced to replace B and is incorporated in the biosynthesis, leading to a mutated natural product. 

Both approaches can potentially greatly increase the diversity of natural compounds. 

Tremendous works dealing with bioinspired total syntheses of secondary metabolites have thus been achieved, providing new insights in the reactivity of biomimetic precursors and occasionally leading to controversy or 

Nicolaou et al. [49] and Uchiro et al. [50] achieved the total syntheses of hirsutellone B in 2009 and 2011, respectively. We recently described a formal total synthesis by forming the key decahydrofluorene (tricyclic) core of hirsutellone in a biomimetic strategy following pathway (b) [47]. As for the synthesis of this important synthetic 

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