Table 1 : Reaching for high-hanging fruit in drug discovery at protein-protein interfaces : Nature

From the following article:

James A. Wells & Christopher L. McClendon

Nature 450, 1001-1009(13 December 2007)

doi:10.1038/nature06526

Ligand	Molecular mass (Da)	PDB identity of complex	Affinity (M)^{^*}	Ligand efficiency (kcal per mol per non-hydrogen atom)^{^†}	References
^*Where a direct binding dissociation constant was not available or was not the lowest measured, the K_i or IC₅₀ was used instead.
^†Ligand-efficiency values for the protein–protein pair are given as binding free energy (-G, in kcal per mol) per non-hydrogen contact atom, because so little of the protein is in contact. Ligand-efficiency values for the small molecule are given as binding free energy (kcal per mol) per non-hydrogen atom³⁶.
^‡The ligand in the X-ray structure is markedly similar to the compound listed. ND, not determined.
IL-2
IL-2 receptor -chain	24,790	1Z92	0.0105	0.11	33
SP4206	663	1PY2	0.06	0.21	31, 34
BCL-X_L
BAD-derived peptide (amino acids 100–126)	3,110	2BZW	0.0006	0.16	89
ABT-737	813	2YXJ	0.0006	0.23	47
HDM2
p53-derived peptide (amino acids 15–29)	1,808	1YCR	0.6	0.12	51
Nutlin-3	581	1RV1^{^‡}	0.09	0.24	53
Benzodiazepinedione	566	1T4E	0.067	0.31	54, 55
HPV E2
E1	24,630	1TUE	0.06	0.14	62
Compound 23	684	1R6N^{^‡}	0.006	0.28	60, 61
ZipA
FtsZ-derived peptide (amino acids 367–383)	2,024	1F47	21.6	0.13	63
Compound 1	425	1Y2F	12	0.23	67
TNF
Subunit protein	17,381	1TNF	ND	ND	90
SP304	548	2AZ5	13	0.17	70