Alkaloids 3

Question 1

Amaryllidaceae family includes…….

snowdrop

daffodil

snowflake

All these species are common in _______________.

Answer 1

Galanthus spp (snowdrop), 
Narcissus spp (daffodil) and 
Leucojum spp (snowflake). 
All these species are common in Europe.

Question 2

Galantamine, lycorine and related alkaloids are biosynthesized from …….

Answer 2

phenylalanine and tyrosine

Question 3

Lycorine and many of the other compounds are…………..

Answer 3

benzylisoquinoline alkaloids

Question 4

Galantamine is benzylisoquinoline alkaloids True or False?

Answer 4

False

galantamine is different (azepine).

Question 5

Galantamine was originally isolated from …………in early 1950’s

Answer 5

Galanthus woronowii

Question 6

Galantamine isolated in 1950s was shown to inhibit …….

Answer 6

acetylcholinesterase

Question 7

State how Galantamine was marketed?

originally in control of anaesthesis to antagonise ________ such as ___________ and derivatives. The use then spread to other fields of medicine.

Answer 7

It has been marketed as a hydrochloride salt (Nivalin®) since 1958; originally in control of anaesthesis to antagonise muscle relaxants such as curare and derivatives. The use then spread to other fields of medicine.

Question 8

Use of Galantamine from 1980s

Answer 8

It was shown to penetrate the blood-brain barrier and enhance cognitive function in Alzheimer’s patients. It has dual action; is a reversible inhibitor of acetylcholinesterase and as well influences nicotinic receptors via an allosteric site which results in the release of acetylcholine.

Note: It does not provide a cure but slows down the reduction of cognitive function.
Used for mild to moderate dementia associated with Alzheimer’s.

Available as tablets and modified release tablets.

Question 9

Galantamine is commercially isolated from…….

Answer 9

Leucojum and Galanthus spp

Question 10

Galantamine is also synthesized and marketed as …..

Answer 10

Reminyl®.

Question 11

Lycorine has antifungal action. True or False?

Answer 11

True

Question 12

Psilocybin & Psilocin are structurally related. True or False?

Answer 12

TRUE

Question 13

Psilocybin & Psilocinare structurally related and are often termed as…..

Answer 13

‘psychedelics’.

Question 14

Facts about Psilocybin and it conversion in the body

Answer 14

Psilocybin occurs in a number of Psilocybe specie

(called magic mushrooms) and is converted to psilocin in the body after ingestion.

Question 15

Facts about Psilocybin and LSD(lysergic acid diethylamide)

Both psilocybin and LSD interact with ________________ and this decreases activity in some parts of the brain, especially the _____________ which is considered to be about the sense of oneself and introspective thought. Hence, the brain becomes less sensitive to _____________.

Answer 15

Both psilocybin and LSD interact with serotonin receptors and this decreases activity in some parts of the brain, especially the default mode network (DMN) which is considered to be about the sense of oneself and introspective thought. Hence, the brain becomes less sensitive to negative thoughts.

Question 16

More recently, …………….. is being considered as a possible therapeutic drug for psychiatric, depression, and anxiety.

Answer 16

Psilocybin

Question 17

State the use of Psilocybin in cancer patients

Answer 17

use it in cancer patients to help reduce anxiety and depression

Question 18

List the side effects of Psilocybin

5

Answer 18

increase in blood pressure, heart rate, and headaches, with a few subjects reporting fear and anxiety.

Question 19

Ergot Indole Alkaloids are biosynthesized from?

Answer 19

tryptophan.

Question 20

Ergot alkaloids’ are so named because…..

Answer 20

they are obtained from the fungus ‘Ergot’ (Claviceps purpurea).

Question 21

What is Ergot?

Ergot is the _____________ stage of the fungus _____________ growing on the rye ________.

Answer 21

Ergot is the sclerotium stage of the fungus Claviceps purpurea growing on the rye Secale cereale.

Question 22

list the number of indole alkaloids with interesting pharmacological applications known 6

Answer 22

physostigmine, psilocin, reserpine, vinblastine.

Synthetic derivatives based on 5 hydroxytryptamin include sumatriptan and zolmitriptan.

Question 23

What is the consequence of ergot being a parasite of cultivated plants (cereal crops)?

Answer 23

is that it gets consumed widely from time to time. The ergot may be collected with the grain and if consumed, will cause the disease ‘ergotism’.

Question 24

what are the symptoms of ergotism?

Answer 24

One symptom of ergotism is the burning sensation and occurrence of gangrene in the body extremities. This results from eating contaminated grain over a long time. Some of the biologically active compounds have a vasoconstriction action on the blood vessels. Other symptoms include hallucinations, epileptic fits, and convulsions.

Question 25

The midwives in the 16th century are known to have collected the ergot and used it to promote childbirth. True or False?

Answer 25

True

Question 26

Different alkaloids have been isolated from ergot. These can be divided into whether they are based on what and what?

Answer 26

lysergic acid or iso-lysergic acid

Question 27

The pharmacologically active alkaloids isolated from ergot are based on……….

Answer 27

The pharmacologically active ones are based on (+)-lysergic acid.

Question 28

The alkaloids can also be divided into those that are water-soluble (___%) and water-insoluble (_______ %). true/false

Answer 28

The alkaloids can also be divided into those that are water-soluble (20 %) and water-insoluble (80 %).

Question 29

List an example of a water-soluble alkaloid and its structure

has a _________ side chain bonded to the C-8 _________ group

Answer 29

Ergometrine (isomer = ergometrinine) – has a 2-amino-propan-1-ol side chain bonded to the C-8 carboxylic acid group

Question 30

State the clinical features of Ergometrine

Clinical features: Produces an ___________ and contraction of the __________, and is used as the ___________ as an intramuscular injection after childbirth for prevention and treatment of _________. Also formulated with _________; together more effective in early pregnancy haemorrhage.

Answer 30

Clinical features: Produces an oxytocic effect and contraction of the blood vessels, and is used as the maleate salt as an intramuscular injection after childbirth for prevention and treatment of haemorrhage. Also formulated with oxytocin; together more effective in early pregnancy haemorrhage.

Question 31

List an example of a water-insoluble alkaloid

Water-insoluble alkaloids (peptide derivatives)
________ is based on lysergic acid amide, which is coupled to ___________, ____________, and ________.

Answer 31

Water-insoluble alkaloids (peptide derivatives)

Ergotamine – is based on lysergic acid amide, which is coupled to proline, phenylalanine, and alanine.

Question 32

State the clinical features of Ergotamine

Acts as an agonist on _________ and _______ receptors; produces __________ – used in the treatment of _________as the tartrate salt

Answer 32

Clinical features: Acts as an agonist on 5-HT and α–adrenergic receptors; produces peripheral vasoconstriction – used in the treatment of migraine attacks as the tartrate salt

Question 33

Bromocryptine is an example of a semi-synthetic derivative of Ergot indole alkaloid used for…..

maybe used to treat _____________ more useful for reducing the release of prolactin due to a tumor and thus___________; also used to treat __________; some use for the treatment of __________

Answer 33

maybe used to treat Parkinsonism (dopamine agonist); more useful for reducing the release of prolactin due to a tumor and thus reduce lactation; also used to treat ACROMEGALY; some use for the treatment of breast cancer.

Question 34

Pergolide and Cabergoline are semi-synthetic derivatives indicated for……

__________ and ____________ (latter also has a similar action to ___________ , but has a longer duration of action) - used to treat __________ (adjunct to __________).

Answer 34

Pergolide and Cabergoline (latter also has a similar action to bromocryptine, but has a longer duration of action) - used to treat Parkinsonism (adjunct to co-beneldopa).

Question 35

What is the therapeutic use of Methysergide?

Methysergide – _______________, used as a prophylactic to treat severe cases of ________ and ___________. Not recommended as a _________due to side effects. However, triptans (e.g. sumatriptan), which are also serotonin ________, modeled on ________, have replaced METHYSERGIDE.

Answer 35

Methysergide – 5-HT antagonist, used as a prophylactic to treat severe cases of migraine and cluster headaches. Not recommended as a first-line treatment due to side effects. However, triptans (e.g. sumatriptan), which are also serotonin agonists, modeled on lysergic acid, have replaced methysergide.

Question 36

What is the therapeutic indication of Lysergic acid diethylamide (LSD-25)?

Answer 36

Lysergic acid diethylamide (LSD-25) – powerful hallucinogenic drug that can lead to severe psychotic states; abused considerably and as little as 50 μg is needed for producing an effect.

Question 37

List examples of therapeutically important alkaloids

Ephedrine, castanospermine, nicotine , arecoline , tubocurarine , colchicine emetine , reserpine , vinblastine and vincristine , strychnine , physostigmine and pilocarpine, and quinine .

Answer 37

Ephedrine (decongestant), castanospermine (AIDS virus), nicotine (antismoking), arecoline (vermicide), tubocurarine (muscle relaxant), colchicine (gout), emetine (amoebic dysentery), reserpine (antihypertensive), vinblastine and vincristine (anticancer), strychnine (appetite stimulant), physostigmine and pilocarpine (miotic), and quinine (malaria).