Crude drugs

Question 1

What is the use of St. John’s Wort?

Answer 1

Treat mild depression
From Hypericum perforatum

Question 2

What’s the use of Ginkgo biloba

Answer 2

Cognitive deficiencies

Question 3

Use of leaves and pods of Senna

Answer 3

Laxative to treat constipation

Question 4

Opium poppy produces which pure compound

Answer 4

Morphine, analgesic from Papaver somniferum

Question 5

Digoxin is a pure compound from

Answer 5

Digitalis glycosides
Foxglove
treat heart failure

Question 6

Taxol from Taxus brevifolia treats

Answer 6

Cancer

Question 7

What is a nutraceutical

Answer 7

Foods having health benefits, but only preventative
e. g ginger, garlic, turmeric

Question 8

What are the roles of natural drug substances in medicine

Answer 8

1. A natural drug
2. Provide basic compound, less toxic and more effective
3. Biological active prototype towards newer and better drugs
4. Modify inactive natural products via chemical means to a potent drug

Question 9

What is the inactive natural product of Taxol?

Answer 9

10-Dasacetylbaccarin

Question 10

Which drug was a prototype for formation of Procaine

Answer 10

Cocaine

Question 11

What are phytochemical aspects of living organisms?

Answer 11

Constituents
Drug Biosynthesis
Classification

Question 12

What’s a constituent

Answer 12

Chemical substance in plant or animal kingdom in one form or the other

Question 13

What are the 2 types of constituents

Answer 13

1. Active- exist pharmacological e. g alkaloids, steroids, glycosides
2. Inert- no inherent pharmacy activity but used in adjunct e. g cellulose, quite, ligin

Question 14

Explain Drug Biosynthesis

Answer 14

Study of biochemical pathways leading to active constituents

Question 15

What is phytochemical classification?

Answer 15

The functional moieties comprising of
1. C and H only e. g Beta-Myrcene
2. C, H and Of only e. g Geraniol
3. O into heterocyclic rings e. g furfur
4. N, S, and P e. g amygdalin
5. Mostly N e. g amino acids
6. Diverse e. g ascorbic acid
7. Mixtures e. g tannins

Question 16

What are natural drug products?

Answer 16

Derived from nature e. g resins, poisons, and exudates
They are drug leads.

Question 17

Define drug leads

Answer 17

Compounds that may be developed into drugs

Question 18

Natural drugs are preferable because they are… (2)

Answer 18

Economic friendly
Renewable

Question 19

Outline the drug discovery process (11)

Answer 19

Biomass
Extraction
Screening (LTS/HTS)
Bioassay guided isolation
Cross screening
Structural elucidation
Large scale isolation
Chemical modifications
Invivo studies
Clinical trials
Drug

Question 20

BRIEFLY explain the long, expensive process.

Answer 20

Biomass (collected and dried)
Extraction (in suitable organic solvent)
Screening (bioassay to assess bioactivity- low throughput screening/high throughput screening)
Bioassay guided isolation(chromatography to separate extracts to purify drug lead)
Cross screening (isolate lead compound)
Structure elucidation (determine 3D structure of drug lead I.e class and present bioactivity)
Large scale isolation (after confirming bioactivity)
Chemical modifications (either synthesis de Novo or enhance it)
Invivo (establish activity,toxicity and efficacy)
Clinical trials (safety and efficacy in humans)
Drug (succeed at trials, product license)

Question 21

State the 5 classes of natural products (PAST Grown)

Answer 21

1. Polyketides
2. Shikimic acid derivatives
3. Tepenes
4. Glycosides
5. Alkaloids

Question 22

What are the 5 classes of Polketides

Answer 22

1. Fatty acids and glycerides
2. Tetracyclines
3. Griseofluvin
4. Erythromycin A
5. Statins

Question 23

What is the formation pathway for polyketides?

Answer 23

Claisen reaction
1. Malonyl-CoA is reduced by Acetyl-CoA
2. Remove extra SCoa and make O double bond again forming Acetoacetly-CoA
3. React with 2 malonyl-CoA to make Poly beta keto ester
4. Reduce to make Fatty acyl-CoA
5. Hydrolyze to make Fatty acids

Question 24

What are fatty acids used for?

Answer 24

Saponifiable with strong NaOH base to make soap
It’s an ester of propane-1, 2, 3-triol

Question 25

Where is Oleic acid from

Answer 25

Olive oil from the family Oleaceae

Question 26

Euphorbuaceae is a source of which fatty acid?

Answer 26

Ricinoleic acid from castor oil
It’s a purgative

Question 27

Alpha linoleic acid and is from

Answer 27

Line seed oil
Linaceae family

Question 28

Tetracyclines are mutants of which organism

Answer 28

Streptomyces aureofaciens

Question 29

What is the spectrum of activity of Tetracyclines?

Answer 29

Broad against G- and G+
And spirochetes, mycoplasmae, chlamydiae
Structure is a vibrating mosithaphala

Question 30

Give 2 semi synthetic tetracyclines

Answer 30

Minocycline
Doxycycline

Question 31

Griseofluvin is an antibiotic from which fungus?

Answer 31

Penicillium griseofulvum

Question 32

What does Griseofluvin treat?

Answer 32

Systemic fungal treatment of hair, mails, skin and feet
Infections caused by trichophyton, epidermophyton and microsporum
Structure has those 4 bold lines drawing a chair attaching the Pentagon to the hexagon

Question 33

Erythromycin A is from which filamentous bacteria

Answer 33

Saccharipolyspora erythrea of genus Streptomyces

Question 34

Erythromycin is used in the treatment of

Answer 34

Legionnaire disease
Respiratory tract infections in penicillin allergies
Structure looks like flying chairs

Question 35

What are Statins used for?

Answer 35

Lower cholesterol production
Structure looks like robot dog with pigtails

Question 36

Give examples of statins

Answer 36

Mevastatin (from Penicillin Citrine and penicillium brevicompactum)

Lovastatin (from Monarchs super and Aspergillus terreus)