Principles of Organic Medicinal Chemistry

331 Pages·2009·7.78 MB·English

by  Rama Rao Nadendla

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Copyright © 2005, New Age International (P) Ltd., Publishers
Published by New Age International (P) Ltd., Publishers
All rights reserved.
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ISBN (13) : 978-81-224-2485-0
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Principles of Organic Medicinal Chemistry is concerned with chemistry, synthesis, struc-
ture activity relationships, properties and uses of drugs of carbon compounds. This book has
primarily been written with the aim of meeting the needs and interests of undergraduate and
graduate pharmacy course according to syllabi of various Indian Universities. The book is a
concise form covering all newer drugs will help the readers to a great extent.
Though several books are available on medicinal chemistry, the material in most of them
is present in a diffused form or highly specialized. In the ever expanding knowledge of the
chemistry of drugs it is very difficult to go through the various textbooks, journals, and
pharmacopoeias. The major objective of writing this book is to present the information in a
lucid, condensed and cohesive form, to cater specially the needs of undergraduate and graduate
students of pharmacy.
It is impossible to express my indebtedness to those authors of various books, articles
and monographs mentioned in bibliography, which became a major source of information for
writing this text. I wish to recall my gratitude to Sri Y.V. Anjaneyulu, Chairman, Chalapathi
Education Society, Guntur, members of Siddhartha Academy, Vijayawada, staff members of
Chalapathi Institute of Pharmaceutical Sciences, Guntur, and Principal and staff members of
KVSR Siddhartha College of Pharmaceutical Sciences, Vijayawada for their kind cooperation.
I am also wish to acknowledge indebtedness to all who have assisted with the completion of the
book. The cooperation of publishers, Messrs New Age International (P) Limited and publishers
is very much appreciated in bringing out this book. The contribution that I received by sus-
tained cooperation of my wife and daughter cann’t be ignored.
I have made every effort to avoid printing errors. However, despite best efforts, some
might have crept in inadvertently. I shall be oblished if these are brought to my notice. Con-
structive suggestions, comments and criticism on the subject matter of the book will be grate-
fully acknowledged, as they will certainly help to improve future editions of the book.
It is hoped that the book will be received favorably as an effective text book by both
students and teachers of pharmacy, science and medical scientists.
Author
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1. Introduction to medicinal chemistry ........................................................................... 1
2. General priciples of drug action...................................................................................3
3. Physico chemical properties of organic medicinal agents........................................ 14
4. Chemistry of prodrugs................................................................................................31
5. Drug metabolism.........................................................................................................41
6. General anesthetics ....................................................................................................52
7. Sedative-hypnotic drugs.............................................................................................61
8. Psychoactive drugs......................................................................................................77
9. Antiepileptic agents..................................................................................................102
10. Cholinergic and anticholinergic drugs ....................................................................121
11. Adrenergic drugs.......................................................................................................149
12. Adrenoreceptor blocking drugs................................................................................170
13. Skeletal muscle relaxants ........................................................................................ 180
14. Antihistamines..........................................................................................................184
15. Narcotic analgesics ................................................................................................... 211
16. Narcotic antagonists................................................................................................. 225
17. Antitussives...............................................................................................................229
18. Non-steroidal antiinflammatory drugs ...................................................................232
19. Local anesthetics.......................................................................................................249
20. Diuretics ....................................................................................................................259
21. Hypoglycemic agents ................................................................................................270
22. Thyroid and antithyroid drugs.................................................................................282
Practice Questions.....................................................................................................290
References ..................................................................................................................315
Index ..........................................................................................................................317
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Introduction to Medicinal
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Chemistry
The subject of medicinal chemistry explains the design and production of compounds that can
be used for the prevention, treatment or cure of human and animal diseases. Medicinal chem-
istry includes the study of already existing drugs, of their biological properties and their struc-
ture-activity relationships.
Medicinal chemistry was defined by IUPAC specified commission as “it concerns the
discovery, the development, the identification and the interpretation of the mode of action of
biologically active compounds at the molecular level”.
Medicinal chemistry covers the following stages:
(i)In the first stage new active substances or drugs are identified and prepared from
natural sources, organic chemical reactions or biotechnological processes. They are
known as lead molecules.
(ii)The second stage is optimization of lead structure to improve potency, selectivity and
to reduce toxicity.
(iii)Third stage is development stage, which involves optimization of synthetic route for
bulk production and modification of pharmacokinetic and pharmaceutical properties
of active substance to render it clinically useful.
Medicinal chemistry is the application of chemical research techniques to the synthesis
of pharmaceuticals. During the early stages of medicinal chemistry development, scientists
were primarily concerned with the isolation of medicinal agents found in plants. Today, scien-
tists in this field are also equally concerned with the creation of new synthetic compounds as
drugs. Medicinal chemistry is almost always geared toward drug discovery and development.
Medicinal chemists apply their chemistry training to the process of synthesizing new
pharmaceuticals. They also work on improving the process by which other pharmaceuticals
are made. Most chemists work with a team of scientists from different disciplines, including
biologists, toxicologists, pharmacologists, theoretical chemists, microbiologists, and
biopharmacists. Together this team uses sophisticated analytical techniques to synthesize and
test new drug products and to develop the most cost-effective and eco-friendly means of pro-
duction.
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