CONTENTS
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INTRODUCTION
DEFINATION
TRADITIONAL DRUG DESIGNING
METHODS OF TRADITIONAL DRUG DESIGNING
INTRODUCTION
 Drug design is the inventive process of finding
new medications based on the knowledge of the
biological target.
In the most basic sense, drug design involves
design of small molecules that
are
complementary in shape and charge to the biomolecular target to which they interact and
therefore will bind to it.
INTRODUCTION
Drug design frequently but not necessarily
relies on computer modeling techniques. This
type of modeling is often referred to as
computer-aided drug design.
Modeling techniques for prediction of binding
affinity are reasonably successful.
TRADITIONAL DRUG DESIGNING
• Traditional drug discovery involves the origin of
drug discovery that evolved in natural sources,
accidental events etc.
• It was not target based and not much systemised as
today.
• Improvement and advancement in pharmaceutical
science and technology made it evolutionised to
much more systemised modern drug discovery.
METHODS OF TRADITIONAL DRUG
DESIGNING
1.
2.
3.
4.
5.
Random Screening
Trial & Error Method
EthnopharmacologyApproach
Serendipity Method
Classical Pharmacology
1. Random Screening
• It includes random screening of synthetic
compounds/chemicals/natural products by
bioassay procedures.
• It involves two approaches
1.Screening for selected class of compounds like
alkaloids, flavonoids, etc
2. Screening of randomly selected plants for selected
bioassays
2. Trail and Error Method
• Trial and error includes berries, roots, leaves
and barks that could be used for medicinal
purposes.
Examples:• Cinchona Bark contains quinine used to reduce
fever in malaria.
• Leaves of Azadirachta indica (Neem) are used
as anti-inflammatory and antibacterial
properties etc.
• Licorice roots are traditionally used to treat
stomach ulcers, bronchitis and sore throats.
3. Ethnopharmacology Approach
• Ethnopharmacology is the study of medicinal
plants used in specific cultural groups.
• It involves the observation, description, and
experimental investigation of indigenous drugs.
• It is based on botany, chemistry, biochemistry,
pharmacology and many other disciplines like
anthropology, archeology, and history.
•Examples:•Andrographis paniculata was used for dysentery
in ethnomedicine and the compounds responsible
for the activity were isolated as andrographolide.
•Morphine from Papaver somniferum,
•Berberine from Berberis aristata,
•Picroside from Picrorrhiza kurroa.
4. Serendipty Method
• “Serendipity” refers to ‘an accidental discovery’
i.e, ‘finding one thing while looking for
something else’
• No scientific discovery has ever been made by
pure luck.
• All happy accidents in science have one point in
common: “each was recognized, evaluated and
acted upon in the light of the discoverer's total
intellectual experience.”
• Examples:• The most important example of this method is
• The discovery of Penicillin by Alexander
Fleming in 1928 while doing research on
influenza.
• One more example is the discovery of
Cisplatin (used in bladder cancer) while
studying E.coli bacteria.
5. Classical Pharmacology
• Also known as Function based approach. Without
the prior identification of drug target.
• Anciently, drug discovery processes were often
based on measuring a complex response in-vivo
such as
i) Prevention of experimentally induced seizures
ii) Lowering of blood sugar
iii) Suppression of inflammatory response
• Examples:Sr. No
Compound
Origin
Uses
1
Acyclovir
Synthetic analog
of cytrabin from a
marine source
It is used to treat
herpese infection
2
Cyclosporin
Fungus
It is used to
prevent tissue graft
rejection
3
Digoxin
Foxglove
Digitalis has been
used since 1775
digoxin remains an
effective drug for
heart failure
4
Vinblastin &
vincristine
Priwinkle
It is used to treat
leukemia and
lymphoma