Stemodane Diterpenes and Diterpenoids: Isolation, Structure Elucidation, Biogenesis, Biosynthesis, Biological Activity, Biotransformations, Metabolites and Derivatives Biological Activity, Rearrangements

Abstract

The scientific activity carried out over forty-five years on stemodane diterpenes and diterpenoids structure elucidation, biogenesis, biosynthesis, biological activity and biotransformations was reviewed.

Organocatalyst Design for the Stereoselective Annulation towards Bicyclic Diketones and Analogues

“…The decalin structure 1 was firstly synthesised in 1950 by the chemists P. Wieland and K. Miescher in its racemic mixture [19], and together with its homologues bicyclo[4.3.0]nonane (HPESW, 2) and bicyclo [5.4.0]undecane (Swaminathan, 3), they represent essential building blocks in natural products synthesis (Figure 1). In fact, these are common scaffolds present in many biologically active compounds and natural molecules, and therefore they represent crucial building blocks in medicinal and pharmaceutical chemistry (Figure 2) [20][21][22][23]. Therefore, the possibility to achieve the stereoselective synthesis of these compounds using organocatalysis, with practically simple synthetic methods as demonstrated in 1971, represents a key point for the total synthesis of various natural products.…”