A General Route to Cyclopeptide Alkaloids: Total Syntheses and Biological Evaluation of Paliurines E and F, Ziziphines N and Q, Abyssenine A, Mucronine E, and Analogues

A full account of the total syntheses of the cyclopeptide alkaloids paliurine E and F, ziziphine N and Q, abyssenine A, and mucronine E is provided. A key feature of the syntheses involves an intramolecular amidation of a vinyl iodide, which allows us simultaneously to address two synthetic challenges associated with cyclopeptide alkaloids: the formation of the enamide and macrocyclization. We also document the use of other strategies for the macrocyclization step, as well as the evaluation of the antibacterial and cytotoxic properties of the natural products and analogues obtained. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)