Novel settlement inhibition oligopeptides containing β-amino acids†

Efficient syntheses of tripeptides containing β-amino acids and their settlement inhibition activities toward two main foulants, the barnacle Amphibalanus amphitrite and the blue mussel Mytilus galloprovincialis, are described. The tripeptide design was inspired by a tripeptide fragment of dolastatin 16, a depsipeptide isolated from the sea hare Dolabella auricularia. Tripeptide with only α-amino acids did not exhibit settlement inhibition, while β-amino acid-containing tripeptides and dipeptides effectively prevented settlement. Made from inexpensive amino acids, these peptides are promising candidates for cost-effective and eco-friendly antifouling additives.