Table 3.

Inhibition of α-thrombin by trimer 9a in presence of exosite 1 or exosite 2 ligands.^a

	logIC50	IC50 (μM)	HS	ΔYa (%)
0 μM	−6.17 ± 0.03	0.67 ± 0.04b	1.5 ± 0.2	79 ± 9
[Hirugen peptide]
3 nM	−6.07 ± 0.03	0.9 ± 0.1	2.5 ± 0.5	44 ± 2
5 nM	−6.10 ± 0.03	0.8 ± 0.1	2.4 ± 0.3	46 ± 2
15 nM	−6.04 ± 0.03	0.9 ± 0.1	3.0 ± 0.7	43 ± 1
[Heparin]
4.2 μM	−6.00 ± 0.04	1.0 ± 0.1	2.2 ± 0.4	71 ± 7
12.8 μM	−5.68 ± 0.03	2.1 ± 0.1	1.8 ± 0.2	80 ± 11
25.0 μM	−5.42 ± 0.02	3.8 ± 0.2	1.7 ± 0.2	81 ± 10
42.6 μM	−5.26 ± 0.06	5.6 ± 0.8	1.2 ± 0.2	~90c
[Octasaccharide H8]
1.0 μM	−5.87 ± 0.02	1.3 ± 0.1	2.3 ± 0.3	58 ± 3
3.0 μM	−5.87 ± 0.04	1.4 ± 0.1	2.6 ± 0.6	54 ± 4
10 μM	−5.78 ± 0.02	1.6 ± 0.1	2.8 ± 0.4	50 ± 2
20 μM	−5.75 ± 0.03	1.8 ± 0.1	2.6 ± 0.5	49 ± 2
[γ′-Fibrinogen peptide]
0.2 μM	−5.94 ± 0.02	1.2 ± 0.1	2.4 ± 0.3	73 ± 8
0.65 μM	−5.95 ± 0.03	1.1 ± 0.1	2.1 ± 0.3	71 ± 8
2.0 μM	−5.92 ± 0.02	1.2 ± 0.1	3.3 ± 0.6	67 ± 4
6.5 μM	−5.88 ± 0.06	1.3 ± 0.2	2.1 ± 0.6	65 ± 7

^aInhibition studies were performed in 20 mM Tris-HCl buffer, pH 7.4, containing 100 mM NaCl, 2.5 mM CaCl₂ and 0.1 % PEG 8000 in PEG20000-coated acrylic cuvettes. S-2366 was used as thrombin substrate and trimer 9a was incubated overnight with thrombin at 25 °C. Logistic equation 1 was used to fit the dose-dependence of the residual thrombin activity to obtain log IC₅₀, HS, Y₀, and Y_M. ΔY = Y_M − Y₀. See ‘Experimental Procedures’ for details.

^bRepresents 1 ± S.E.

^cApproximate value because Y₀ was not well defined.