Carbohydrates are considered as promising templates for the display of multiple copies of antimicrobial peptides. Herein, we
describe the design and synthesis of chimeric structures containing two or four copies of the antimicrobial peptides
KKLFKKILKYL-NH2 (BP100) and KKLfKKILKYL-NH2 (BP143) attached to the carbohydrate template cyclodithioerythritol
(cDTE) or α-D-galactopyranoside (Galp). The synthesis involved the preparation of the corresponding peptide aldehyde followed
by coupling to an aminooxy-functionalized carbohydrate template. After purification, the multivalent display systems were obtained
in high purities (90–98%) and in good yields (42–64%). These compounds were tested against plant and human pathogenic bacteria
and screened for their cytotoxicity on eukaryotic cells. They showed lower MIC values than the parent peptides against the bacteria
analyzed. In particular, the carbopeptides derived from cDTE and Galp, which contained two or four copies of BP100, respectively,
were 2- to 8-fold more active than the monomeric peptide against the phytopathogenic bacteria. These results suggest that
preassembling antimicrobial peptides to multimeric structures is not always associated with a significant improvement of the
activity. In contrast, the carbopeptides synthesized were active against human red blood cells pointing out that peptide preassembly
is critical for the hemolytic activity. Notably, peptide preassembly resulted in an enhanced bactericidal effect
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