prognosides

Prognosides are a class of chemical compounds that were initially proposed as hypothetical intermediates in the biosynthesis of certain natural products, particularly polyketides and non-ribosomal peptides. The term "prognoside" was introduced in the 1980s by German chemist Hans Grisebach to describe a hypothetical structure that could explain the formation of complex natural products through enzymatic processes.

The concept of prognosides suggests that enzymes might temporarily bind or modify substrates in a way that resembles a glycoside linkage, even if the final product does not retain this structure. This idea was inspired by the well-studied glycosylation processes, where sugar moieties are attached to aglycones to form glycosides. Prognosides were proposed as a mechanism to facilitate the transfer of functional groups or intermediates during biosynthesis, particularly in the assembly of large, structurally diverse molecules.

While the term "prognoside" itself is not widely used in modern biochemical literature, the underlying principles—such as enzymatic activation and intermediate stabilization—have been incorporated into more established theories of natural product biosynthesis. Research in this area has since shifted toward detailed mechanistic studies of enzyme-catalyzed reactions, particularly in the fields of polyketide synthase (PKS) and non-ribosomal peptide synthase (NRPS) pathways.

Prognosides remain an interesting historical concept, illustrating early attempts to bridge gaps in our understanding of complex biochemical processes. Their study contributed to the broader development of biosynthetic theories, which continue to influence drug discovery and synthetic biology today.