This document is a report submitted by Rabia Sattar to Sir Inam about chemical libraries. It defines a chemical library as a collection of stored chemicals used for high-throughput screening or manufacturing. Chemical libraries consist of chemicals with associated data on structure, purity, quantity, and properties stored in a database. The document discusses the purpose of chemical libraries for drug discovery screening, methods for generating and designing libraries through organic synthesis, and requirements for storing and managing libraries over time.

1. ASSIGNMENT OF
CHEMISTRY
• TOPIC CHEMICAL LIBRARY
• SUBMITTED BY
• RABIA SATTAR
• TO
• SIR INAM
• ROLL NO #3013
• UOE(OKARA)

2. CHEMICAL LIBRARY
• A chemical library or compound library is a
collection of stored chemicals usually used
ultimately in high-throughput screening or
industrial manufacture. The chemical library can
consist in simple terms of a series of stored
chemicals. Each chemical has associated
information stored in some kind of database with
information such as the chemical structure,
purity, quantity, and physiochemical
characteristics of the compound.

3. CONTENTS
• 1 Purpose
• 2 Generation of chemical libraries
• 3 Design and optimization of chemical libraries
• 4 Storage and management

4. PURPOSE
• In drug discovery high-throughput screening, it is desirable to
screen a drug target against a selection of chemicals that try to take
advantage of as much of the appropriate chemical space as
possible. The chemical space of all possible chemical structures is
extraordinarily large. Most stored chemical libraries do not typically
have a fully represented or sampled chemical space mostly because
of storage and cost concerns. However, since many molecular
interactions cannot be predicted, the wider the chemical space that
is sampled by the chemical library, the better the chance that high-
throughput screening will find a "hit"—a chemical with an
appropriate interaction in a biological model that might be
developed into a drug.
• An example of a chemical library in drug discovery would be a series
of chemicals known to inhibit kinases, or in industrial processes, a
series of catalysts known to polymerize resins.

5. GENERATION OF CHEMICAL
LIBRARIES
• Chemical libraries are usually generated for a specific
goal and larger chemical libraries could be made of
several groups of smaller libraries stored in the same
location. In the drug discovery process for instance, a
wide range of organic chemicals are needed to test
against models of disease in high-throughput
screening. Therefore, most of the chemical synthesis
needed to generate chemical libraries in drug discovery
is based on organic chemistry. A company that is
interested in screening for kinase inhibitors in cancer
may limit their chemical libraries and synthesis to just
those types of chemicals known to have affinity for ATP
binding sites or allosteric sites.

6. GENERATION OF CHEMICAL LIBRARIES
• Generally, however, most chemical libraries
focus on large groups of varied organic
chemical series where an organic chemist can
make many variations on the same molecular
scaffold or molecular backbone. Sometimes
chemicals can be purchased from outside
vendors as well and included into an internal
chemical library.

7. DESIGN AND OPTIMIZATION OF
CHEMICAL LIBRARIES
• Chemical libraries are usually designed by chemists and
chemoinformatics scientists and synthesized by organic chemistry
and medicinal chemistry. The method of chemical library generation
usually depends on the project and there are many factors to
consider when using rational methods to select screening
compounds.[2] Typically, a range of chemicals is screened against a
particular drug target or disease model, and the preliminary "hits",
or chemicals that show the desired activity, are re-screened to
verify their activity. Once they are qualified as a "hit" by their
repeatability and activity, these particular chemicals are registered
and analysed. Commonalities among the different chemical groups
are studied as they are often reflective of a particular chemical
subspace. Additional chemistry work may be needed to further
optimize the chemical library in the active portion of the subspace.
When it is needed, more synthesis is completed to extend out the
chemical library in that particular subspace by generating

8. generating more compounds that are very similar to the original hits. This new
selection of compounds within this narrow range are further screened and then taken
on to more sophisticated models for further validation in the Drug Discovery Hit to
Lead process.

9. STORAGE AND MANAGMENT
• The "chemical space" of all possible organic chemicals is large and
increases exponentially with the size of the molecule. Most
chemical libraries do not typically have a fully represented chemical
space mostly because of storage and cost concerns.
• Because of the expense and effort involved in chemical synthesis,
the chemicals must be correctly stored and banked away for later
use to prevent early degradation. Each chemical has a particular
shelf life and storage requirement and in a good-sized chemical
library, there is a timetable by which library chemicals are disposed
of and replaced on a regular basis. Some chemicals are fairly
unstable, radioactive, volatile or flammable and must be stored
under careful conditions in accordance with safety standards such
as OSHA.

10. REFERENCE
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