features and have been synthesized via a novel acid-catalyzed head-to-side-chain concomitant cyclization/cleavage reaction on oxime resin. The methodology gave rapid access to the anabaenopeptin scaffold by taking advantage of a combined solid-phase/solution-phase synthetic strategy. Also, as side-products of the synthesis, large C2-symmetric 38-member cyclic peptides ring bearing two endocyclic lysine side-chains