DRUG DEVELOPMENT Search for New Drugs A' SERENDIPITY

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DRUG DEVELOPMENT Search for New Drugs A.
SERENDIPITY
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SERENDIPITYNew Drugs

• Penicillins
• Fleming 1941
• Penicillium notatum

• Benzodiazepines
• Sternbach 1958
• Diazepam (Valium)

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Discovery of Benzodiazepine Ring Structure
Chlordiazepoxide
quinazoline-N-oxide
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SERENDIPITYNew Drugs

• Lithium salts
• Cade 1948
• Li Carbonate (Carbolith)

• Sulfonylureas
• Carbutamide
• Tolbutamide

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SERENDIPITYNew Drugs
Antiemetics
diphenhydramine
Cl-theophylline
dimenhydrinate
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SERENDIPITYNew Drugs
6- Mercaptopurine (Purinethol)
Azathioprine (Imuran)
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SERENDIPITYNew Indications
Acetanilide
acetaminophen (Tylenol)

• Amantadine
• (Symmetrel)

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SERENDIPITYNew Indications
Flucytosine
Disulfiram
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SERENDIPITYNew Indications
Thalidomide
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DRUG DEVELOPMENT Search for New Drugs B.
PHARMACOLOGICAL SCREEN

• RANDOM
• various tests
• all compounds
• not cost-effective

• RATIONALLY DIRECTED
• antimalarials
• antibiotics from microbes
• drug metabolites
• acetanilide - acetaminophen
• imipramine - desipramine
• phenylbutazone oxyphenbutazone

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DRUG DEVELOPMENT Search for New Drugs C.
EXTRACTION FROM NATURAL SOURCES

• Antibiotics
• Vitamins
• Hormones
• Vaccines

• Morphine
• Cocaine
• Taxol