Biogenetic speculation and biosynthetic advances

The present article highlights selected instances of the formulation of biogenetic schemes which over the past half century have contributed to our current understanding of the biosynthesis of secondary metabolites. These are mostly formed from a small number of primary precursors, which can often be identified by structural analysis. Representative examples of the role Of Speculation are discussed with particular emphasis on homo- and heterocyclic polyketides and amino acid derived products.