A compound library is like a library of books where different titles and different content is available at a single place. Storage of compounds and their related data makes a compound library where different compounds are collected and arranged for some specific purposes. The compound screening of the library are placed, maintained and stored in a very scientific way. Drug discovery is one of the major purposes of making compound libraries. Recent technologies to organize and design chemical compound library have made the process of drug discovery a more interesting and attractive research area for the scientists and remarkable successes have been seen after the fast growing technologies have made its research easier [1]. The most important thing after construction of compound library is its screening that is looking for the best suited compound relevant to question we are seeking the answer for and the compound that is biologically more active. In order to screen and then select a compound different schemes and protocols have been developed by the experts who have made the process of selection more efficient, faster and better than before. Recent methodologies of library designing include fragment-based methods and structure based methods, both of which utilize efficient and latest softwares which ensure implementation of small molecule screening library efficiently.

Designing and screening a compound library is a very lethargic type of work that needs extraordinary care but the elaborate description of chemicals and advices by experts on their implementation has made quite easier. Results oriented and efficient molecules are easier to choose now by using recently developed technologies. Scientists are searching and researching new and more efficient drugs using these technologies against many vital diseases. A library of small molecules which are biologically active is reasonably and systematically supported by a thoroughly furnished database with all the knowledge of the molecules included in the chemical library screening. The description usually contains chemical structure, physical chemical and pharmacological properties and purity of the compound [2].

Screening a compound library is the most important task of all the steps involved in drug discovery research. Different chemical and high throughput assays are there for the purpose of screening best suited compound. A thorough chemical library can make the process of drug discovery easier against a specific disease. A large compound library is divided into small molecule libraries in order to more specify our search and to decreases the lethargic screening of un-necessary compounds. This division is based upon some structural and pharmacological properties of the compound having logic of being derivatives of the same parent compound. Therefore it is quite easier to screen a subset of drug rather than a whole library, and there are increases chances of finding more suitable compound as drug of interest in lesser time with lesser effort and lesser consumption of reagents. Chemical screening is also done for the compounds but there is always a need of re-screening for confirmation of drug activity in specific conditions [3]. Before using the drug in patients, its activity is confirmed through different in vitro and in vivo studies. It has to pass through several phases of pre-clinical and clinical trials [4]. Latest advances in technology and different development of different software tools have made the process of screening of small molecules quite easier. It is now much more convenient to design, screen and further confirm a library in a very systematic way [5].

1. Zhou, J., Chemical Library Design. Methods in Molecular Biology. Vol. 685. 2011: Humana Press.
2. Schneider P, e.a., Self-Organizing Maps in Drug Discovery: Compound Library Design, Scaffold-Hopping, Repurposing Current Medicinal Chemistry, 2009.
3. Su GH, e.a., A Novel Histone Deacetylase Inhibitor Identified by High-Throughput Transcriptional Screening of a Compound Library. Cancer Res, 2000.
4. Huggins DJ, e.a., Rational Methods for the Selection of Diverse Screening Compounds. ACS Chem. Biol., 2011.
5. Gaillard Y, e.a., Use of high-performance liquid chromatography with photodiode-array UV detection for the creation of a 600-compound library application to forensic toxicology. Journal of Chromatography A, 1997.