This presentation delves into the fascinating world of pharmaceuticals, exploring the diverse nature of drugs and their sources. From natural compounds to synthetic creations, we'll uncover the origins of these crucial medications and their impact on healthcare.

1. Drug
French: Drogue – a dry herb
The single active chemical entity present in a
medicine that is used for diagnosis,prevention,
treatment/cure of a disease.
In 1966, WHO defination
“Drug is any substance or product that is
used or is intended to be used to modify or
explore physiological systems or pathological
states for the benefit of the recipient.”

2. Nature of Drugs
Introduction:
All drugs are chemicalentities with simple or complex molecules.
Drugs can be classifiedon basisof:
1. OrganicCompounds
a. Weakly acidic
b. Weakly basic
c. Non-electrolytes
2. Inorganic Compounds
3. PhysicalProperties
a. Solid b. Liquid c. Gas
4. DrugSize

3. Nature of Drugs
Organic Compounds
Theseare the drugs relating or belonging to the class of chemical
compounds having a carbon basis.
a. Weakly acidic.Eg Aspirin, Penicillin
b. Weakly basic.Eg Morphine, Chloroquine
c. Non-electrolytes. Eg Alcohol, Diethylether

4. Nature of Drugs
Inorganic Compounds
Theseare the drugs relating or belonging to the class of
compounds not having a carbon basis.
1. Lithium carbonate
2. Ferrous sulphate
3. Magnesium hydroxide

5. Nature of Drugs
Physical Properties:
1. SOLID e.g. Paracetamol, Furosemide, Ampicillin,etc.
2. LIQUID e.g. Ethanol, Gyceryltrinitrate, Propofol, castor oil, etc.
3. GAS e.g. Nitrous Oxide

6. Nature of Drugs
Drug Size and Shape:
• Most of the drugscome under the rangeof 100-1000daltons.
Accordingto their size, drugsbind specifically to their bindingsite.
• Molecules less than 100Ddon'tgenerally havetheir unparalleledfeaturessuch
asshape, size, configuration,chirality etc.
• Molecules having their MW of more than1000Dcannotreadilydiffusewithinthe
cells/tissues of the body.
Few examples-
1. Lithium(7D)
2. Heparin(10-20D)
3. Gonadotropins(>30D)
• Drugshape must be antonymous to the receptor sitelike thatof lock & key so that
they can bind easilyandpromote their actionsaccordingly.Most of the drugs
show chirality.

7. Sources
of
Drugs
Sources
of
Drugs Drugs are obtained from a variety of sources.
Plants
Animals
Microbes Minerals
Synthetic
Chemistry
Biotechnology

8. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
4. Microbes
3. Minerals
2. Animals
1. Plants
Sources
of
Drugs
Sources
of
Drugs Plants Many plants contain biologically active substances and are the oldest
source of drugs.
Clues about medicinal plants were obtained from traditional systems of
medicine prevalent in various parts of the world;
e.g. use of opium, belladonna, ephedra, cinchona, curare, foxglove,
sarpagandha, qinghaosu has been learnt from Egyptian, Greek, Aztec,
Ayurvedic, Chinese and other systems of in medicine.
Chemically the active ingredients of plants fall in several categories:
a. Alkaloids
b. Glycosides
c. Oils
Other plant products like
tanins are astringent;
gums are demulcents and act as suspending agents in liquid dosage forms.
Glycerine is a viscous, sweet liquid used as vehicle for gum/throat paint.
Resins and balsams are used as antiseptic and in cough mixtures.
The antimalarial drug artemisinin is a sesquiterpene endoperoxide obtained
from a Chinese plant.

9. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
4. Microbes
3. Minerals
2. Animals
1. Plants
Sources
of
Drugs
Sources
of
Drugs a. Alkaloids: These are alkaline nitrogenous bases having potent activity, and
are the most important category of vegetable origin drugs. examples are:
morphine, atropine, ephedrine, nicotine, ergotamine, reserpine, quinine,
vincristine, etc. They are mostly used as their water soluble hydrochloride/
sulfate salts.
b. Glycosides: These compounds consist of a heterocyclic nonsugar moiety
(aglycone) linked to a sugar moiety through ether linkage. Cardiac
glycosides (digoxin, ouabain) are the best known glycosidic drugs. The
active principle of senna and similar plant purgatives are anthraquinone
glycosides. Aminoglycosides (gentamicin, etc.) are antibiotics obtained
from microorganisms, and have an aminosugar in place of a sugar moiety.
c. Oils: These are viscous, inflammable liquids, insoluble in water. Fixed
(nonvolatile) oils are calorie yielding triglycerides of higher fatty acids;
mostly used for food and as emollients, e.g. groundnut oil, coconut oil,
sesame oil, etc.
Castor oil is a stimulant purgative.

10. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
4. Microbes
3. Minerals
2. Animals
Plants
Sources
of
Drugs
Sources
of
Drugs
Exploration of activity of organ extracts in the late 19th and early 20th century
led to introduction of animals parts as medicines.
Examples:
a. Adrenaline
b. Thyroxine
c. Insulin
d. Liver extract (Vitamin B12)
Antisera and few vaccines are also produced from animals.

11. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
4. Microbes
3. Minerals
nimals
Plants
Sources
of
Drugs
Sources
of
Drugs
Few minerals used as medicines:
a. Iron salts,
b. Calcium salts,
c. Lithium Carbonate,
d. Magnesium/ Aluminium hydroxide
e. Iodine

12. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
4. Microbes
nerals
nimals
Plants
Sources
of
Drugs
Sources
of
Drugs 1. Many antibiotics obtained from :
• Fungi
• Actinomycetes
• Bacteria
Examples of Antibiots :
a. Penicillin
b. Gentamicin
c. Tetracycline
d. Erythromycine
e. Polymyxin B
f. Actinomycin D (Anti-Cancer)
2. Some enzymes e.g.
a. Diastase from Fungus
b. Streptokinase from streptococci
3. Vaccines are produced by use of microbes.

13. 6. Biotechnology
ynthetic
Minerals
nimals
Plants 5. Synthetic
Microbes
Minerals
nimals
Plants
Sources
of
Drugs
Sources
of
Drugs Synthetic Chemistry came into existence in 19th Century.
Now it is largest source of medicines.
Synthetic drugs have the advantage of purity and uniformity of the product.
They can be manufactured in any quantity as per need, in contrast to drugs
obtained from plants.
Entirely synthetic family of drugs:
a. Benzodiazepins
b. Thiazides
c. Benzimidazolles
d. Fluoroquinolones, etc
Many drugs synthesised to target specific biomolecules . E.g.
A. ACE inhibitors
B. Glycoprotein Iib/IIIa receptor antagonist
C. HIV-reverse transcriptase inhibitors, etc.

14. 6. Biotechnology
ynthetic
Minerals
nimals
Plants
thetic
crobes
nerals
Plants
Sources
of
Drugs
Sources
of
Drugs Several Drugs (peptides and proteins) are now produced by recombinant DNA
technology.
E.g.
a. Human Insulin,
b. Human growth hormone
c. Altaplase
c. Interferone, etc
Newer drugs of biotechnological origin:
a. Monoclonal antibodies
b. Regulator peptides
c. Erythropoietin
d. Other growth factors
Protein therapeutics is rapidly expanding because customized proteins
can be produced