Both enantiomers of FF8181-A were synthesized through optical resolution from the known Diels-Alder reaction product in 15 steps. The absolute configuration of the natural product was determined to be 1S,5S,5aS,9aS,9bS.

A 14-membered macrocycle with an allene and a furan strategically located at across the ring from each other is synthesized using an allene ring closing metathesis reaction. Upon treatment of the macrocycle with a catalytic amount of Pd(OAc)(2) and other additives, the first transannular [4+3] cycloaddition occurred to yield 37% of a tetracyclic compound containing the ABC ring structure of the...

Eight-membered carbocycles are found in a wide variety of natural products that exhibit a broad range of biological and medicinal activities (cf. the most potent anticancer drug, taxol). However, the synthesis of eight-membered carbocycles is quite challenging as traditional approaches are met with entropic and enthalpic penalties in the ring-forming transition states. These negative effects ca...

The main directions of Natural Products Chemistry in the Third Millennium are summarized.

A tandem reaction involving a Rh(I)-catalyzed two-component [(5+2)+1] cycloaddition and an aldol condensation has been developed to construct the tricyclo[6.3.0.02,6]undecane skeleton and its heteroatom-imbedded analogues. Meanwhile, this method has been successfully applied to natural product synthesis for the first time. The present strategy enables a straightforward approach to the natural l...

Historically, natural products have been used since ancient times and in folklore for the treatment of many diseases and illnesses. Classical natural product chemistry methodologies enabled a vast array of bioactive secondary metabolites from terrestrial and marine sources to be discovered. Many of these natural products have gone on to become current drug candidates. This brief review aims to ...

The fawcettimine class of Lycopodium alkaloids consists of over 60 natural products. Typically, these tetracyclic compounds contain a single quaternary carbon center and are derived biosynthetically from the lycopodane core through an oxidative rearrangement reaction. In 1959, the first member of this class, fawcettimine (1), was isolated by Burnell in the Blue Mountain Range of Jamaica. Inubus...

The natural product montamine was originally assigned as a homodimer of moschamine linked by a N-N' bond at the serotonin side-chain. A total synthesis of the reported structure has shown this to be incorrect. Analysis of the spectroscopic data suggests that the dimerization site has been incorrectly assigned, and montamine is likely to be a 4,4'-bismoschamine natural product previously describ...

There are a vast number of interesting and useful compounds that are readily found in nature. Mother Nature has acquired ingenious ways of generating molecular diversity in living cells responsible for regulation of various biochemical events. This has inspired research into the synthesis of biologically active compounds for use as antibiotics or in cancer therapy, for example. This account pro...

Over recent years several examples of natural ribosomally synthesized circular proteins from a diverse range of organisms have been discovered. They are special molecules, whose precursors must be posttranslationally modified to join the N to C termini with a head-to-tail peptide bond. This feature appears to have a range of potential advantages over their linear counterparts, since they are le...