Table 2.

Average values of descriptors characterizing polar molecular surface area, H-bond donors, H-bond acceptors, partition coefficient and rotatable bonds for ordinary molecules, ligands and ligands with different protein-binding potentials

Descriptor*	Small molecules†	Average values	Standard error	Number of molecules
PSA	Molecules	111.81	1.79	2,184
	Ligands	230.59	2.79	2,176
	Ligands (≤ 3)	225.71	2.80	2,072
	Ligands (4-9)	304.28	15.67	80
	Ligands (≥ 10)	406.83	33.10	24
Donor	Molecules	1.51	0.04	2,184
	Ligands	3.97	0.07	2,176
	Ligands (≤ 3)	3.87	0.07	2,072
	Ligands (4-9)	5.24	0.43	80
	Ligands (≥ 10)	8.21	0.90	24
Acceptor	Molecules	3.35	0.05	2,184
	Ligands	5.87	0.09	2,176
	Ligands (≤ 3)	5.74	0.09	2,072
	Ligands (4-9)	7.69	0.53	80
	Ligands (≥ 10)	11.00	1.18	24
AlogP98	Molecules	2.87	0.05	2,184
	Ligands	0.81	0.06	2,176
	Ligands (≤ 3)	0.92	0.06	2,072
	Ligands (4-9)	-1.33	0.25	80
	Ligands (≥ 10)	-1.80	0.38	24
LogP	Molecules	0.77	0.08	2,184
	Ligands	-2.27	0.10	2,176
	Ligands (≤ 3)	-2.10	0.10	2,072
	Ligands (4-9)	-5.06	0.50	80
	Ligands (≥ 10)	-8.11	0.96	24
RotBond	Molecules	4.88	0.09	2,184
	Ligands	7.49	0.11	2,176
	Ligands (≤ 3)	7.43	0.11	2072
	Ligands (4-9)	8.00	0.50	80
	Ligands (≥ 10)	11.33	1.19	24

* PSA, polar molecular surface area; Donor, H-bond donor counts; Acceptor, H-bond acceptor counts; AlogP98, log of the partition coefficient, atom-type value, using latest parameters; LogP, log of the partition coefficient; RotBond, number of rotatable bonds. ^†Molecules, ACD-SC-derived ordinary molecules; Ligands, sc-PDB-derived ligands; Ligands (≤ 3), ligands covering ≤ 3 folds; Ligands (4-9), ligands covering 4-9 folds; Ligands (≥ 10), ligands covering ≥ 10 folds.