In 2007 Enamine Ltd and UORSY (Ukrorgsyntez Ltd) launched a joint project in order to establish a systematic chemically validated approach to synthesis of "in-stock-tomorrow" building blocks that consist of up to 21 heavy atoms and therefore can be used in medicinal chemistry and drug discovery. The average values for number of heavy atoms, MW and cLogP of the tangible building blocks are 18.3, 272 and 2.3, respectively. Full database (20 556 947 structures) and other relevant data including prices can be found at the library download page. The golden set of tangible building blocks (4 721 351 structures, containing up to 16 heavy atoms) have also been posted at Accelrys® Available Chemicals Directory. These databases are updated at least two times a year.
The main chemical classes of tangible building blocks are listed in the table below.
|Type of Building Blocks||Number of structures|
|Primary and Secondary Amines||4 484 000|
|Carboxylic Acids||1 009 000|
|Amino Acids||191 000|
|Alkylating and Arylating Agents||679 000|
|Sulfonyl Chlorides||26 000|
|Aldehydes and Ketones||317 000|
|Alkyl- and Arylhydrazines||43 000|
|Amidoximes and Amidines||118 000|
|Aryl bromides and Aryl iodides||743 000|
|Boronic acids||7 000|
|Alkyl- and Arylazides||7 600|
|Terminal acetylenes||34 000|
Rigorously validated chemical procedures ensure high feasibility and cost effectiveness of tangible building blocks and fragments. About 8 500 building blocks were synthesized in 2009 with lead time of 4-6 weeks and feasibility of 80%. Over 4 000 of these compounds were selected from the database of tangible building blocks and ordered by pharma and biotech companies worldwide at fixed prices ranging from 200 to 800 € per gram. Weekly progress reports on the synthesis of the ordered tangible building blocks and fragments are provided to the customers.