1 OPR (5s)-5-amino-8-carbamimidamido-4-oxooctanoic acid 1.000 2 ARM Deoxy-methyl-arginine 0.750 3 U4G N-octylguanidine 0.750 4 YF5 Agmatinamic acid 0.750 5 A5R Amino{[(4s)-4-amino-9-carboxy-5-oxononyl]amino}methaniminium 0.700