MEDICINAL CHEMISTRY
332 Medicinal Chemistry 2 + 0 +0 (2 Credits)
Chemistry, synthesis, structure –activity relationship and medicinal use
Sulfonamides, sulfones, antibiotics, antimalarial, amoebicides, trypanocides, antiemetics,
antineoplastics and antiviral agents. Chemistry, synthesis, structure-activity relationships,
synthesis, analogue and medicinal of alkaloids, glycosides, lipids and volatile oils
The pharmaceutical industry is an important segment of the chemical industry not because of its
volume of chemicals, which is usually small, but because these chemicals are high priced per
volume and because it employs about 30% of all technical personnel in Chemical Manufacturing.
The pharmaceutical industry is a technologically intensive industry; it is not uncommon for drug
companies to spend 10% of their sales on research expenditures. A typical new drug might take
15 years and over $500 million R & D. This includes discovery, animal trials, limited human trials,
patent applications, process development, large-scale clinical trials, regulatory approval, and
marketing. Only 3 out of 15,000 developmental drugs usually make it to full market.
Pharmaceutical preparations are drugs formulated and fabricated into their final form for direct
consumption (tablets, capsules, etc.). The industry has grown rapidly in the past 30 years especially
in pharmaceutical production. Examples of biological products are bacterial and virus vaccines,
serums, plasmas, and other blood derivatives. Medicinals and botanicals include bulk organic and
inorganic medicinal chemicals and bulk botanical drugs and herbs. Examples are alkaloids,
anesthetics, barbituric acid and derivatives, caffeine, hormones, insulin, morphine, penicillin,
quinine, aspirin, sulfa drugs, and vitamins.
Characteristics of the Pharmaceutical Industry
General characteristics of the pharmaceutical industry are the following:
(1) use of multistage batch processes rather than continuous flow.
(2) high level of product purity .
(3) management which is usually technically oriented.
(4) high promotional costs
(5) use of generic names as well as brand or trademark names
, (6) expensive and lengthy drug testing and clinical trials.
(7) strict regulation by the authorities. E.g. NAFDAC, FDA, SON, etc.
Sources of Pharmaceuticals
There are 5 sources of pharmaceuticals. By value of products, fermentation is probably the most
important, while by tonnage, chemical synthesis is dominant. Fermentation is used for antibiotics
such as penicillin, streptomycin, tetracycline etc. and for modification of the steroid nucleus.
Chemical synthesis provides drugs such as the psychotropic’s and antihistamines. Animal extracts
are the third source and provide various hormones and such things as liver extract for treatment of
anemia. Biological sources lead to vaccines and serums valuable, for example, for immunization
against smallpox and diphtheria. Vegetable extracts are the final source, and provide steroid
precursors and alkaloids such as quinine and atropine.
Pharmacodynamics
Medicinal chemists must be generally knowledgeable about pharmacodynamics, that is, the effect
of drugs upon biological systems. In addition to being aware of the state-of-the-art understanding
of the biological mechanisms that underlie the particular diseases for which they are endeavoring
to discover drug therapy they should know the basis of the various in-vitro and in-vivo tests that
the biologists employ to evaluate both the potential efficacy and side-effect liability of the
synthesized compounds. In a general sense the primary and often even the secondary biological
tests of drugs for a particular disease target are in vitro tests that can be run rather quickly,
inexpensively, and on small amounts of compound.
Evaluation of a new chemical entity’s (NCE) propensity to cause side effects is as important as
efficacy testing. Even if a compound shows an encouraging level of the desired activity, a lack of
selectivity can cause it to induce a number of undesirable pharmacological effects thus precluding
its further development. The medicinal chemist must be able to interpret the results of the tests run
on his/her compounds and use this information as a guide to further synthetic work.
PROPERTIES OF A DRUG
The goal of pharmaceutical research is the discovery of “ideal drugs”. The properties of an ideal
drug can be summarized as follows:
332 Medicinal Chemistry 2 + 0 +0 (2 Credits)
Chemistry, synthesis, structure –activity relationship and medicinal use
Sulfonamides, sulfones, antibiotics, antimalarial, amoebicides, trypanocides, antiemetics,
antineoplastics and antiviral agents. Chemistry, synthesis, structure-activity relationships,
synthesis, analogue and medicinal of alkaloids, glycosides, lipids and volatile oils
The pharmaceutical industry is an important segment of the chemical industry not because of its
volume of chemicals, which is usually small, but because these chemicals are high priced per
volume and because it employs about 30% of all technical personnel in Chemical Manufacturing.
The pharmaceutical industry is a technologically intensive industry; it is not uncommon for drug
companies to spend 10% of their sales on research expenditures. A typical new drug might take
15 years and over $500 million R & D. This includes discovery, animal trials, limited human trials,
patent applications, process development, large-scale clinical trials, regulatory approval, and
marketing. Only 3 out of 15,000 developmental drugs usually make it to full market.
Pharmaceutical preparations are drugs formulated and fabricated into their final form for direct
consumption (tablets, capsules, etc.). The industry has grown rapidly in the past 30 years especially
in pharmaceutical production. Examples of biological products are bacterial and virus vaccines,
serums, plasmas, and other blood derivatives. Medicinals and botanicals include bulk organic and
inorganic medicinal chemicals and bulk botanical drugs and herbs. Examples are alkaloids,
anesthetics, barbituric acid and derivatives, caffeine, hormones, insulin, morphine, penicillin,
quinine, aspirin, sulfa drugs, and vitamins.
Characteristics of the Pharmaceutical Industry
General characteristics of the pharmaceutical industry are the following:
(1) use of multistage batch processes rather than continuous flow.
(2) high level of product purity .
(3) management which is usually technically oriented.
(4) high promotional costs
(5) use of generic names as well as brand or trademark names
, (6) expensive and lengthy drug testing and clinical trials.
(7) strict regulation by the authorities. E.g. NAFDAC, FDA, SON, etc.
Sources of Pharmaceuticals
There are 5 sources of pharmaceuticals. By value of products, fermentation is probably the most
important, while by tonnage, chemical synthesis is dominant. Fermentation is used for antibiotics
such as penicillin, streptomycin, tetracycline etc. and for modification of the steroid nucleus.
Chemical synthesis provides drugs such as the psychotropic’s and antihistamines. Animal extracts
are the third source and provide various hormones and such things as liver extract for treatment of
anemia. Biological sources lead to vaccines and serums valuable, for example, for immunization
against smallpox and diphtheria. Vegetable extracts are the final source, and provide steroid
precursors and alkaloids such as quinine and atropine.
Pharmacodynamics
Medicinal chemists must be generally knowledgeable about pharmacodynamics, that is, the effect
of drugs upon biological systems. In addition to being aware of the state-of-the-art understanding
of the biological mechanisms that underlie the particular diseases for which they are endeavoring
to discover drug therapy they should know the basis of the various in-vitro and in-vivo tests that
the biologists employ to evaluate both the potential efficacy and side-effect liability of the
synthesized compounds. In a general sense the primary and often even the secondary biological
tests of drugs for a particular disease target are in vitro tests that can be run rather quickly,
inexpensively, and on small amounts of compound.
Evaluation of a new chemical entity’s (NCE) propensity to cause side effects is as important as
efficacy testing. Even if a compound shows an encouraging level of the desired activity, a lack of
selectivity can cause it to induce a number of undesirable pharmacological effects thus precluding
its further development. The medicinal chemist must be able to interpret the results of the tests run
on his/her compounds and use this information as a guide to further synthetic work.
PROPERTIES OF A DRUG
The goal of pharmaceutical research is the discovery of “ideal drugs”. The properties of an ideal
drug can be summarized as follows:
