Table 1.

Inhibition of biotinylated vitronectin binding to the α_vβ₃ receptor.

Entry	Cpd	Structure	αvβ3 IC50 [nm][a]	Rp/n [b]
1	5	cyclo[DKP‐RGD]‐Val‐Ala‐PTX (aliphatic scaffold)	14.8±3.9	–
2	6	cyclo[DKP‐RGD]‐Val‐Ala‐PTX (aromatic scaffold)	27.3±9.8	–
3	7	(cyclo[DKP‐RGD])2‐Val‐Ala‐PTX	4.0±0.1	3.4
4	8	(cyclo[DKP‐RGD])3‐Val‐Ala‐PTX	1.2±0.5	7.6
5	9	(cyclo[DKP‐RGD])4‐Val‐Ala‐PTX	1.3±0.3	5.3
6	1	cyclo[DKP‐RGD]	4.5±0.1	–

[a] IC₅₀ values were calculated as the concentration of compound required for 50 % inhibition of biotinylated vitronectin binding, as estimated by GraphPad Prism software. All values are the arithmetic mean ± the standard deviation (SD) of triplicate determinations. [b] The relative potency Rp is obtained by dividing the IC₅₀ of the monovalent reference 6 by the IC₅₀ of each multivalent conjugate. Rp/n values were calculated by dividing Rp of the multivalent conjugates by the valency (n) of each conjugate.22