Organic Synthesis Challenging Natural Products and New Frontiers

Organic Synthesis Challenging Natural Products and New Frontiers 

The search for biologically active compounds (natural and synthetic) continued to be a significant inspiration for organic synthesis. Asymmetric catalysis, new synthetic reactions, and advances in separation techniques (HPLC) and analytical techniques (NMR and mass spectrometry) support these advances. In 1995, Kyriacos Costa (K.C.) Nicolaou (1946- ) at Scripps Research Institute reported the total synthesis of brevetoxin B (see the figure on page 375). This toxic substance is produced by algae in red tide and is very deadly to fish. It binds to sodium channels in membranes of muscle and nerve cells producing an excessive influx of Na.  

Brevetoxin B has 23 chiral centers as well as 11 trans-fused rings. While it has far fewer chiral centers than palytoxin (page 331), the 

Schlenk s hydrocarbon and Dougherty s polymeric radical anion 

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