introduction to medicinal chemistry

1. MEDICINAL CHEMISTRY I
BY AKLILU
1

2. 2
MEDICINAL CHEMISTRY I

3. CHAPTER ONE: INTRODUCTION
 Definition and its relation to other disciplines
 Source and classification of drugs
 Nomenclature of drugs
3

4. Definition:
• It is chemistry-based discipline, also involving aspects of
biological, medical and pharmaceutical sciences.
• It is applied science that is focused on the design (or discovery)
of new chemical entities (NCEs) and their optimization and
development as useful drug molecules for the treatment of
disease processes”.
4

5. Definition:
• Structure-activity relationship (SAR) is the relationship
between chemical structure and pharmacological activity for a
series of compounds.
5
 It is concerned with
o the invention, discovery, design, identification and preparation of
biologically active compounds,
o the study of their metabolism, the interpretation of their mode of action at
the molecular level and
o the construction of structure-activity relationships (SAR).

6. Definition:
• Medicinal chemistry covers three critical steps:
6
Discover step
Optimization
step
Development
stage

7. 7
Discover step
• Involving choice of therapeutic
target (receptor, enzyme& target
group)
• Identification and production of
new active substances
interacting with selected targets.
• Such compounds called
LEADCOMPOUND.
Optimization step
• Which deals with
improvement of lead
compound
• The optimization process
takes primarily into account
the increase in potency,
selectivity
Development
stage
Whose purpose is
continuation of
improvement of
pharmacokinetic properties

8. 8
Reading assignment
Origin of medicinal chemistry

9. Relation to other disciplines
• Medicinal chemistry is disciplines at the intersection of chemistry,
especially synthetic organic chemistry, and pharmacology and
various other biological specialties, Biochemistry, Molecular
biology.
9

10. Relation to other
disciplines
• It relate to
10
Chemistry
Medicinal
chemistry

11. Source and classification of drugs
What are drugs?
• Drugs are chemical substances that are used to prevent or treat
diseases in humans, animals and plants.
• They may also be used for making a medical diagnosis or for
restoring, correcting, or modifying physiological functions.
11

12. What are drugs?
• Drugs can act as poisons if taken in excess.
• overdoses of paracetamol can cause coma and death.
• In addition to their beneficial effects, most drugs have
non-beneficial biological effects.
• Aspirin, which is commonly used to alleviate headaches, may also
cause gastric irritation and bleeding.
• These unwanted effects are commonly referred to as
side effects.
12

13. Natural
Sources of drugs
• Generally sources of drugs are
13
Plants Animals Synthetic
Semi
synthetic

14. Classification of drugs
There is no homogeneous system for classifying
drugs
Drugs are classified in a number of different ways
depending on where and how the drugs are being used.
• Chemical structures
• Pharmacological Action
• Drugs can treat different types of diseases
14

15. 1. Chemical structures:
alkaloids, steroids, glycosides, etc
15

16. 2. Pharmacological Action:
• Site of action: Cellular site e.g., loop diuretic,
catecholamine uptake inhibitor
• Body system e.g. cardiovascular, alimentary
16

17. 3. Drugs can treat different types of diseases:
• 1-Infectious diseases: Born (transmitted) from person to person by outside agents,
bacteria (pneumonia, salmonella), viruses (common cold, AIDS), fungi (thrush,
athletes foot), parasites (malaria)
• 2-Non-infectious diseases: disorders of the human body caused by genetic
malfunction, environmental factors, stress, old age etc. (e.g. diabetes, heart disease,
cancer. Haemophilia, asthma, mental illness, stomach ulcers, arthritis).
• 3-Non-diseases: alleviation of pain (analgesic), prevention of pregnancy
(contraception) , anesthesia.
17

18. Nomenclature of drugs
• There are basically three classes of drug names which is
recognized by drug companies and regulatory bodies
18
Chemical names
Generic/Non-proprietary /Approved names
Trade/Brand names
/Proprietary

19. 1. Chemical names
• Are the scientific (IUPAC) names, based on the molecular
structure of the drug.
• Are useful for chemists or technical personnel
• Not suitable for common use in prescribing drugs
19
Paracetamol
N-(4-hydroxyphenyl)-acetamide

20. 2. Generic names
• They are official names assigned by national regulatory agencies
• It avoids the confusion of giving several names to the same drug
Example
• Co-trimoxazole, Diclofenac, Omeprazole, Paracetamol
20

21. 3. Trade/Brand names
• Names given to the drug by the manufacturing and marketing company
• In most cases one drug could have so many (multiple) trade/brand names
21
Acetaminophen has many
trade names such as
• Paracetamol
• Tylenol
• Paramol
• Panadol
• cadimol
• Capol etc.

22. 22
Thank you for watching
Join blu pharmacy on telegram
for more books and ppt
https://t.me/pharmacyRxx
Facebook
Log in or sign up to send message
https://www.facebook.com/akyeako