“…The C7 center is readily epimerizable and its configuration changes www.eurjoc.orgfrom substrate to substrate, as evidenced by previous syntheses. [3][4][5] The structure and stereochemistry of product 2b were confirmed by undertaking a series of 1 H COSY, HMBC, HSQC, NOESY, and NOE experiments. Thus, the ambitious super cascade had worked, and the product it produced (i.e., 2b) represents the ABCDE ring skeleton of the pectenotoxins, albeit with the incorrect stereochemistry at C11; this fault was introduced by limitations to classical chemistry earlier in the substrate synthesis, not by the highly effective super cascade.…”