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In our previous studies on the allylic rearrangement for formation of enediynes from 1,2-dialkynylallyl alcohols and the related allylic systems, we have established various methodologies for regio- and stereoselective transformation under mild reaction conditions.1 Among them, the acid-catalyzed rearrangement of a cyclic allyl alcohol 1 at rt furnished exclusively the 10-membered ring enediyne 3. Rearran- gement of 1 also took place in pH 8.5 at 37 C in the presence of DNA and cleavage of DNA was observed.2 In the present work, we report on the synthesis of 1 and 2 through the intramolecular Nozaki reaction (CrCl2-NiC12) of iodoalkyne with aldehyde (bond disconnections a and b) as the key step. Rearrangement of allylic methoxyacetate 2 was catalyzed by Eu(fod)3 at rt to give the cyclic enediyne 4 in good yield.3,4 Enediynes 3 and 4 as well as the precursors 1 and 2 exhibited DNA cleavage activity, compounds 2 and 4 are much more potent and cause strand cleavage atμM level.