Enediynes are a class of bacterial natural products characterized by either nine- and ten-membered rings containing two triple bonds separated by a double bond. Many of these compounds are capable of undergoing Bergman cyclization. The resulting diradical, a 1,4-dehydrobenzene derivative, is capable of abstracting hydrogen atoms from the sugar backbone of DNA which results in strand scission. This high reactivity with DNA makes the substances toxic. They are being researched as antitumor agents. Several of the naturally occurring enediynes have entered clinical trials against cancer  and in Japan neocarzinostatin is used clinically.
Three classes of enediynes exist:
The enediyne group in those compounds is often called a warhead.
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- Designed Enediyne Antitumor Agents
- Development of Photoswitchable Enediyne Antibiotics