Introduction to Medicinal Chemistry
Drug basics
o Drugs: a chemical that measurably changes physiological function of an organism
(ex. catnip, heroin)
o Not clearly defined from medicine
o Drugs generally have many effects, whereas medicine usually intends to cure or
provide relief
o Changes on body by drugs: activity level, consciousness, coordination, incoming
sensory information, mood, emotion
o Drugs inhibit, block, (and less often) speed up the action of receptors, enzymes,
and signaling proteins
o Identification markers
Origin – plant, animal, fungi, synthetic
Chemical composition – organic, inorganic
Preparation – pure vs mixture
Delivery – oral, parenteral, inhaled, rectal
Legal vs illegal
Helpful vs harmful
Type – analgesic, depressant, stimulant, antibacterial, etc.
o Placebos are quantifiable and are beneficial because they avoid side effects
Research, development, and testing
1. New chemical entity (NCE) is noted
2. Physical and chemical structure established
3. In vitro (petri dish) testing for effect and safety
4. Animal testing (Identify LD50: what dosage causes half of the population to die)
5. Submitted to Food and Drug Administration (FDA) as an Investigational new drug
(IND)
6. Clinical trials:
a. Phase I: Test on healthy patients to determine safety and dosing
b. Phase II: Test on small numbers of patients to determine efficacy and to
further explore safety
c. Phase III: Test in large trials in large patient groups for statistical reliability
Methods of administration
o Oral
Delivered by mouth
Advantages: convenient, non-invasive
Disadvantages: % of absorption low, might interact with food and
beverages, stomach acid, absorption slow
o Parenteral
Delivered by injection: subcutaneous (under the skin), intramuscular (into
the muscle), or intravenous (into the vein)
Advantages: fast delivery (sub < intramusc < intraven), precise control
amount for intravenous injections
Drug basics
o Drugs: a chemical that measurably changes physiological function of an organism
(ex. catnip, heroin)
o Not clearly defined from medicine
o Drugs generally have many effects, whereas medicine usually intends to cure or
provide relief
o Changes on body by drugs: activity level, consciousness, coordination, incoming
sensory information, mood, emotion
o Drugs inhibit, block, (and less often) speed up the action of receptors, enzymes,
and signaling proteins
o Identification markers
Origin – plant, animal, fungi, synthetic
Chemical composition – organic, inorganic
Preparation – pure vs mixture
Delivery – oral, parenteral, inhaled, rectal
Legal vs illegal
Helpful vs harmful
Type – analgesic, depressant, stimulant, antibacterial, etc.
o Placebos are quantifiable and are beneficial because they avoid side effects
Research, development, and testing
1. New chemical entity (NCE) is noted
2. Physical and chemical structure established
3. In vitro (petri dish) testing for effect and safety
4. Animal testing (Identify LD50: what dosage causes half of the population to die)
5. Submitted to Food and Drug Administration (FDA) as an Investigational new drug
(IND)
6. Clinical trials:
a. Phase I: Test on healthy patients to determine safety and dosing
b. Phase II: Test on small numbers of patients to determine efficacy and to
further explore safety
c. Phase III: Test in large trials in large patient groups for statistical reliability
Methods of administration
o Oral
Delivered by mouth
Advantages: convenient, non-invasive
Disadvantages: % of absorption low, might interact with food and
beverages, stomach acid, absorption slow
o Parenteral
Delivered by injection: subcutaneous (under the skin), intramuscular (into
the muscle), or intravenous (into the vein)
Advantages: fast delivery (sub < intramusc < intraven), precise control
amount for intravenous injections
