Patent ID: 7342089

Claim:
A synthetic cyclic peptide of the structural formula: wherein: R 1 is H, NH 2 , or R 2 is —C(═O)—NH— or —NH—C(═O)—; R 3 is 4-imidazolyl or 3-indolyl; R 4a and R 4b are each optional ring substituents, and when one or both are present, are the same or different and independently hydroxyl, halogen, alkyl, or aryl groups attached directly or through an ether linkage; R 5 is —NH 2 or —NH(C═NH)NH 2 ; R 6 is 1- or 2-naphthyl or 3-indolyl, optionally with one or two ring substituents, and when one or both ring substituents are present, are the same or different and independently hydroxyl, halogen, alkyl, or aryl groups attached directly or through an ether linkage; R 8 is H, NH 2 , a lower aliphatic C 1 to C 4 linear or branched alkyl chain, a C 1 to C 4 aralkyl, or a C 1 to C 4 aliphatic moiety with a terminal amino group; R 9 is H, a lower aliphatic C 1 to C 4 linear or branched alkyl chain, a C 1 to C 4 aralkyl, or a C 1 to C 4 aliphatic moiety with a terminal amino group; R 10 is an aliphatic L- or D-amino acid, an N-acylated L- or D-amino acid or a linear or branched C 1 to C 17 alkyl, aryl, heteroaryl, alkene, alkenyl, or aralkyl chain; R 11 and R 12 are each independently H or a C 1 to C 4 linear or brarfched alkyl chain, on the proviso that both R 11 and R 12 are not H; x is 1 to 4, and y is 1 to 5, provided that x+y is 2 to 7; and z is 2 to 5.