Studies Directed to the Total Synthesis of ET 743 and Analogues Thereof: An Expeditious Route to the ABFGH Subunit

Abstract
In model studies directed to the total synthesis of Et743, a strategic S−C bond formation in systems 26 and 27 was demonstrated. It was further shown that Pictet−Spengler cyclization leading to spiro product 33 exhibits very high stereoselection.