Bergman cydization

In another recent development in aromatic synthesis, the Bergman cydization [7] is beginning to be exploited for preparative purposes. This process has been studied for many years because of its importance with regard to the biological action of several marine antitumor antibiotics such as calicheamicin [58] and because of its interesting reaction mechanism [8]. Now, more and more synthetic applications are beginning to be reported in the literature [59]. 

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