Total synthesis and confirmation of the revised structures of azaspiracid-2 and azaspiracid-3

The 39 steps: The recently proposed revised structures of azaspiracid-2 and -3 (see picture), the two most potent members of the azaspiracid family, have been confirmed through the total syntheses of the two compounds. These 39-step syntheses represent a major improvement over the first-generation synthesis of azaspiracid-1 (50 steps). (Chemical Equation Presented). © 2006 Wiley-VCH Verlag GmbH & Co. KGaA.