The natural antibiotic triostin A (1) is based on a conformationally rigid disulfide-bridged cyclo-octadepsipeptide scaffold. This bicyclic core structure provides a perfect preorganization of two covalently attached quinoxalines resulting in sequence-specific bis(intercalation) of the chromophores in double-stranded DNA. Herein for the first time the corresponding cyclopeptide has been synthesized as a scaffold instead of the cyclodepsipeptide of triostin A by solid-phase peptide synthesis followed by bis(cyclization) in solution. Furthermore, when in contact with DNA the bicyclic peptide

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