A NEW APPROACH TO THE SYNTHESIS OF ARISTOLACTAMS - TOTAL SYNTHESIS OFCEPHARANONE-A AND CEPHARANONE-B

An efficient, concise and tactically new synthesis of aristolactams is described. The key step is the aryne-mediated cyclization of an amino carbanion derived from a phosphorylated halobenzamide derivative. Hor ner reaction, radical cyclization and ultimate deprotection complete t he synthesis of the phenanthrene lactam alkaloids. The viability of th e strategy is further illustrated by the synthesis of cepharanone A an d B.