Table II.

Commonly Screened Chemical Databases

Database	Type	No. of compoundsa	Website
PubChem	Public	30 million	http://pubchem.ncbi.nlm.nih.gov
ChEMBL	Public	1 million	https://www.ebi.ac.uk/chembldb/index.php
NCI Set	Public	140,000	http://dtp.nci.nih.gov/index.html
ChemSpider	Public	26 million	http://www.chemspider.com
CoCoCo	Public	7 million	http://cococo.unimore.it/tiki-index.php
TCM	Public	32,000	http://tcm.cmu.edu.tw
ZINC	Public	13 million	http://zinc.docking.org
ChemBridge	Commercial	700,000	http://www.chembridge.com
Specs	Commercial	240,000	http://www.specs.net
Asinex	Commercial	550,000	http://www.asinex.com
Enamine	Commercial	1.7 million	http://www.enamine.net
Maybridge	Commercial	56,000	http://www.maybridge.com
WOMBAT	Commercial	263,000	http://www.sunsetmolecular.com
ChemDiv	Commercial	1.5 million	http://www.chemdiv.com
ChemNavigator	Commercial	55.3 million	http://www.chemnavigator.com
ACD	Commercial	3,870,000	http://accelrys.com/products/databases/sourcing/available-chemicals-directory.html
MDDR	Commercial	150,000	http://accelrys.com/products/databases/bioactivity/mddr.html

^aApproximate numbers