“…Given the interesting biological activity of these butenolides, especially the activity against pancreatic cancer, it is not surprising that several approaches toward the synthesis of analogues of these natural products is of interest. The synthesis of butenolides has been accomplished using metal-catalyzed cyclization approaches, radical cyclizations, acid-catalyzed lactonization, hydrolysis and saponification of quinones, and in an enantiomerically pure form. , For symmetrical butenolides like 9 , the most common synthetic approach tends to mimic the postulated biosynthetic pathway, , wherein simple aryl pyruvic methyl esters are dimerized in the presence of a base. A representative example is summarized in Scheme .…”