• Total Synthesis of Nannocystin Ax.

      Poock, Caroline; Kalesse, Markus; Hemholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2017-09-01)
      The total synthesis of nannocystin Ax in an overall yield of 11% with 14 steps as the longest linear sequence is reported. Nannocystin Ax is a cytotoxic 21-membered depsipeptide and was isolated from the myxobacterial genus Nannocystis sp. The synthesis uses a vinylogous Horner-Wadsworth-Emmons reaction (HWE) and a vinylogous Mukaiyama aldol reaction (VMAR) as the key steps for the construction of the polyketide fragment. The macrocycle was closed via a macrolactamization reaction using COMU.