Patent ID: 8632992

Claim:
A compound of formula (I): wherein: A is R 1 is selected from H, an amino protecting group and an amino blocking group; n is an integer from 1 to 20; each R 2 is independently an amino acid side chain, wherein at least one R 2 is selected from —CH 2 —CH 2 —CH 2 —CH 2 —NR 4a R 4b , —CH 2 —CH 2 —CH 2 CH 2 —N + R 4a R 4b R 4c and —CH 2 —CH 2 —CH 2 —NH—C(═NR 5a )NR 5b R 5c ; R 3 is acyl; each R 4a is independently selected from hydrogen, alkyl and aryl; each R 4b is independently selected from alkyl and aryl; each R 4c is independently selected from hydrogen, alkyl and aryl; each R 5a is independently selected from hydrogen, alkyl and aryl; each R 5b is independently selected from alkyl and aryl; and each R 5c is independently selected from hydrogen, alkyl and aryl, wherein when R 2 is —CH 2 —CH 2 —CH 2 —CH 2 —N + R 4a R 4b R 4c , the compound further comprises a counteranion.