Recent trends in medicinal chemisry research fundamentalls

1. Welcome
To
11th Annual Research Congress -2019
KARPAGAM ACADEMY OF HIGHER EDUCATION
14th December 2019

2. RECENT RESEARCH TRENDS IN
MEDICINAL CHEMISTRY
RESEARCH
Dr. R. VALLIAPPAN
PROFESSOR
DEPARTMENT OF CHEMISTRY
ANNAMALAI UNIVERSITY
ANNAMALAI NAGAR 608 002

3. Celebrating the Periodic Table, one of
the most significant achievements in
science
This year marks the 150th Anniversary
of the Periodic Table of Chemical
Elements. 1869-2019
Centenary year of 1919-2019 IUPAC
Nomenclature

4. NATIONAL SCIENCE DAY MOTO
• The theme of National Science Day 2019 -
"Science for the People and the People for
Science."

6. DEFINITION
• Medicinal Chemistry – It deals with the
Chemistry of Drugs – The design and synthesis
of organic compounds as drugs, have become
major and closely interwined disciplines

7. STRUCTURE ACTIVITY RELATIONSHIP
• The basis of understanding Medicinal
Chemistry lies in an awareness of the
relationships between the chemistry of a
particular compound or group of compounds
and their actions with the body which are
known as structure activity relationships(SAR)

8. Mode of action
• The mechanism by which the compound
influences the biological systems, which is
known as its mode of action
• The objective of these studies is to improve
the beneficial or therapeutic effects of a drug,
while at the same time minimizing
undesirable side effects.

9. The Relationship of Medicinal
Chemistry to other disciplines
Chemistry and Pharmaceutics and
Biochemistry  biopharmaceutics
 
Medicinal
Chemistry  Pharmacology  Internal Medicine
 
Biology and Toxicology and
Microbiology Pathology

10. DRUGS
• Drugs – A drug is defined as a chemical which
is used for modifying physiological systems.
• Example: Anesthetics, Analgesics, Antipyretics,
Antiseptics

11. CHEMOTHERAPEUTIC AGENT
• A Chemotherapeutic agent is a substance that
inhibits or destroys infectious organisms, such
as pathogenic bacteria or parasites or a
cancerous growth, which has invaded a host
• Pharmacology – old Greek means – POISON
- New means – Drug

12. PHARMACEUTICS
• Pharmaceutics is the discipline of
Pharmacology that deals with the process of
turning a new chemical entity (NCE) into a
medication to be used safely and effectively

13. Why we need new drugs?
Man has been in search of chemicals, which
can be used to control the disease, caused
by microorganisms.
The pharmacological properties of organic
substances have been studied on different
pathogenic organisms in vitro to find out
compounds with physiological activity and
design new chemotherapeutic agents.

14. Why we search for a new drug?
• Since many of the currently available drugs have
undesirable side effects, are ineffective against
new or reemerging micro organisms(bacteria or
fungi) or develop a rapid resistance, there is an
urgent need of a next generation of new agents,
which overcome the above disadvantages.
• The search is oriented to find new antibacterial
and antifungal agents, which may selectively
attack the organisms without inhibiting any
biochemical system of the host.
• Man has been in search of chemicals, which can
be used to control the disease, caused by
microorganisms

15. PROCESS
In the invention or discovery of new drug whether it is from the Natural resources,
i.e., from Biological source, - (animal origin or plant origin) or synthesized from
Chemicals (organic or inorganic)
- Biological means – Isolation, identification, purification, characterization and
preliminary screening for biological activities.
- Chemical means – Preparation/Synthesis, characterization (Physical properties
Colour, odour, nature (liquid, solid, gas) – melting point,
- Chemical – structural identification – Elemental analysis, Functional group
identification, evidence – spectral characterization – UV, IR, NMR, Mass, etc.
- Biological screening

16. Introduction
It is fundamental for an organic chemist to be able to identify, or
characterize, the new compound that he/she has just made.
Sometimes this can be achieved by a chemical means, such as
determining the elemental composition and molecular weight.
If the compound has been made previously, it is possible to compare
physical properties (boiling points / melting points, etc ) with literature
values.
Chemical tests can be used to determine whether certain functionalities
are present or absent.
But, these are not sufficient for either complex molecules or new
molecules that have never been made before.
Tests can be either destructive or non-destructive. (Combustion which
gives elemental analysis is destructive, whereas NMR is non-destructive
- you can recover your sample).
Ideally, chemists want techniques that use small amounts of
compounds, are non-destructive, quick and give unambiguous results.
Spectroscopic techniques generally meet almost all of these requirements

17. The four most common are:
Infrared spectroscopy (IR spectroscopy observes the vibration of bonds,
and gives information about which functionalities are present).
Mass Spectrometry (MS provides information concerning the mass of the
molecule, and sometimes about its structure).
Nuclear Magnetic Resonance Spectroscopy (NMR spectroscopy provides
information about the numbers and environments of all the hydrogens (and
Carbons and Fluorines) in a molecule. Probably the most important
technique).
Ultra Violet Spectroscopy (UV Spectroscopy deals with electronic
transitions, and gives information mainly about multiple bonds and
conjugation).
The Electromagnetic Spectrum
Visible, IR and UV light, microwaves and radio waves are all examples of
electromagnetic radiation. They all travel at the same speed (the speed of light, 3x108
m/s), but differ in their wavelength and frequency.
The frequency, ν, is the number of complete wavecycles to pass a fixed
point in one second. (Usually in Hz, which means cps).
The wavelength, λ, is the distance between any two peaks of the wave.

21. no O-H
str
no N-H
str
no sp
or sp2
C-H str

27. In vitro - studies
• In vitro study is deals with the microorganisms
which were grown in the laboratory and
tested for various functions
• In vivo – means animal model studies for
various drugs designed

28. BACTERIOLOGICAL CULTURE
LABORATORY

29. BACTERIALOLOGICAL TEST PLATES

30. Gram negative bacteria

31. Gram positive bacteria

32. ANTIBACTERIAL SENSTIVITY TEST

33. ANTIBIOTICS
• These are chemical substances produced by
micro organisms having the property of toxic
(or) inhibiting the growth of or destroying
the other microorganisms in low
concentrations.
• Antibiotics are toxic and they also kill the
host tissues besides the microorganisms
which cause the disease

34. IN VIVO STUDIES
(ANIMAL MODEL)

35. ACUTE TOXICITY STUDIES
• The Lethal dose 50 (LD50) test determines the dosage of a
substance that kill 50% of the animals given that dosage.
The LD50 value is that dosage which kills 50% of the
animals. The LD50 value for a substance will vary according
to the species involved. The substance may be
administered any number of ways, including orally,
topically, intravenously, or through inhalation. The most
commonly used species for these tests are rats, mice,
rabbits, and guinea pigs. Substances tested might include

36. ACKNOWLEDGEMENTS
• Sincere thanks to
• Dr. S. Ravi, Professor and Head, Department of
Chemistry, Karpagm University, Coimbatore
• Dr. A. Thangamani, Associate Professor,
Karpagm University, Coimbatore
• All the Faculty members, Research Scholars,
students and authorities of the Karpagam
University and the organizers of this Annual
Research Congress 2019.

37. MY SINCERE THANKS TO
Future pillars of our Nation
– Today’s Functions celebratees
ALL THE STUDENTS OF
CHEMISTRY DEPARTMENT