The present invention provides a peptide of formula (I) or a pharmaceutical salt thereof wherein “m”, “n”, “p”, and “q” represent integers and are selected from 0 and 1; and “r” is comprised from 1 to 10; a linker biradical of formula (II), which is connecting an alpha carbon atom of an amino acid located at position “i” in the peptide sequence of formula (I) with an alpha carbon atom of an amino acid located at position “i+4” or “i+7” in the peptide sequence of formula (I); a C-terminal end corresponding to —C(O)R4; and a N-terminal end corresponding to —NHR5. The peptides of the invention show anticancer activity and an appropriate half-life and stability. Formula (I).