Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

CH 456 Medicinal Chemistry > Chapter 20 > Flashcards

Chapter 20 Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

____ are: an infective agent
typically consists of a nucleic acid molecule in a protein coat
too small to be seen by light microscopy
able to multiply only within the living cells of a host

A

Viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are types of viral diseases?

A 
common cold
flu (influenza)
herpes
human immunodeficiency virus (HIV/AIDS)
human papillomavirus (HPV)
mumps, measles and rubella
viral pneumonia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

viral nucleic acid is covered by a protein coat of repeating units called?

A

capsids

either icosahedral (spherical) or helical symmetry

repeating units reduce the number of genes devoted to production of the viral coat and simplify the process of viral assembly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the 5 stages of the life cyle of viruses?

A

Adsorption: a virion has to first bind to the outer surface of a host cell. This involves a specific molecule on the outer surface of the virion binding to a specific protein or carbohydrate present in the host cell membrane.

Penetration and uncoating: different viruses introduce their nucleic acid into the host cell by different methods. Some inject their nucleic acid through the cell membrane; others enter the cell intact and are then uncoated.

Replication and transcription: viral genes can be defined as early or late. Early genes take over the host cell so that viral DNA and/or RNA can be synthesized.

Synthesis and assembly of nucleocapsids: late genes direct the synthesis of capsid proteins and these self-assemble to form the capsid.

Virion release: naked virions are released by cell lysis while viruses with envelopes are usually released by budding from host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the 4 general principles for good drug protein targets for viruses?

A

They are important to the life cycle of the virus such that their inhibition or disruption has a major effect on infection.

They bear little resemblance to human proteins, thus increasing the chances of good selectivity and minimal side effects.

They are common to a variety of different viruses and have a specific region which is identical in its amino acid composition. This makes the chances of developing a drug with broad antiviral activity more likely.

They are important to the early stages of the viral life cycle, which means that their disruption/inhibition reduces the chances of symptoms and of the virus spreading through the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

True or False: Most of the drugs which are active against DNA viruses have been developed against herpesviruses

A

True,

cold sores, genital herpes, chicken pox, shingles, eye diseases, mononucleosis, Burkitt’s lymphoma, Kaposi’s sarcoma

aciclovir has a nucleoside-like structure and contains the same nucleic acid base as deoxyguanosine (nucleoside primarily effective)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

inhibitors of tubulin polymerization and have been used to treat genital warts caused by ______

A

papillomavirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

_____ was used to treat cytomegalovirus (CMV)(antisense therapy)

A

formivirsen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What activates aciclovir (nucleoside)?

A

Triphosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

HIV drugs are grouped into five drug classes

A

nucleoside reverse transcriptase inhibitors (NRTIs)
- also includes a few nucleotide reverse

transcriptase inhibitors (NtRTIs)
non-nucleoside reverse 
transcriptase inhibitors (NNRTIs)
protease inhibitors (PIs)
entry or fusion inhibitors
integrase inhibitors (INSTIs)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

__________ inhibit the viral reverse transcriptase, either by competing with natural nucleosides (NRTIs) or by reducing its catalytic activity (NNRTIs

A

Reverse transcriptase inhibitors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Nucleoside reverse transcriptase inhibitors (NRTIs):

A

Lack a 3’-OH for attachment of the next nucleotide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

_______ was originally developed as an anticancer agent and the first drug to be approved for use in the treatment of AIDS

A

Zidovudine (aka azidothymidine, AZT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

______ target a hydrophobic allosteric site on reverse transcriptase

A

Non-nucleoside reverse transcriptase inhibitors (NNRTIs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

______ relies on a viral protease to properly cleave viral proteins in preparation for creating new viral particles

A

HIV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

C-C motif chemokine receptor (CCR5) are G-protein–coupled receptor recognized by HIV and CCR5 antagonists inhibit HIV recognition of a prospective host cell

A

Entry or fusion inhibitors

Selzentry)

17
Q

What are the 4 kinds of Integrase inhibitors (INSTIs)

A

HIV integrase

Raltegravir (Isentress) was the first integrase inhibitor (2007)

Elvitegravir was the second integrase inhibitor (2012)

Dolutegravir (2013)

18
Q

____ is a enzyme responsible for integrating viral DNA into the host genome

A

HIV integrase

19
Q

______ is active against Human Endogenous Retroviruses (HERVs) and possibly Epstein-Barr Virus, which have been suggested in the pathogenesis of relapsing-remitting MS

A

Raltegravir (Isentress)

20
Q

what are the drugs for Pre-exposure prophylaxis (PrEP) against HIV infection

A

Tenofovir disoproxil/emtricitabine (trade name Truvada)
a fixed-dose combination of two antiretroviral drugs used for the treatment of HIV/AIDS developed by Gilead Sciences
300 mg of tenofovir disoproxil (NtRTI)
200 mg of emtricitabine (NRTI)

21
Q

______ is a retrovirus containing RNA as its genetic material, and is responsible for AIDS.

A

HIV

22
Q

The two main viral targets for anti-HIV drugs are the enzymes ____ and ____.

A

reverse transcriptase and protease

23
Q

_____ is a group of viruses responsible for a number of diseases and range from the seasonal flu to recent global diseases such as swine flu (H1N1 virus) and bird flu (H5N1 virus)

A

Influenza virus

24
Q

______ is the only oral influenza antiviral approved for use in Canada

______ is an inhaled medication
both are viral neuraminidase inhibitors

A

oseltamivir (Tamiflu)

zanamavir (Relenza)

both are viral neuraminidase inhibitors
neuraminidase is involved in the budding of new viruses from infected cells

25
Q

How do neraminidase inhibitors work?

A

which prevent virions from being released from the surface of infected cells.

26
Q

The flu virus contains (−)ssRNA and has two glycoproteins called ____ and ______ in its outer membrane.

A

haemagglutinin (HA) and neuraminidase (NA)

27
Q

______ binds to the sialic acid moiety of glycoconjugates on the outer surface of host cells leading to adsorption and cell uptake.

_____ catalyses the cleavage of sialic acid from glycoconjugates. It aids the movement of the virus through mucus and releases the virus from infected cells after budding.

A

HA, NA

28
Q

True or False: There are four important binding pockets in the active site. The sialic acid moiety is distorted from its normal chair conformation when it is bound.

A

True

29
Q

The mechanism of the enzyme-catalysed reaction is proposed to go through an _______. Inhibitors were designed to mimic this state by introducing an endocyclic double bond.

A

endocyclic sialosyl cation transition state

30
Q

_____ is where attachment takes place between the virus and the host cell
on the canyon floor there is a pore which opens into a hydrophobic pocket within the VP1 protein
pocket is either empty or occupied by a small molecule called a pocket factor

A

Canyon

31
Q

Phase III clinical trials for ______ demonstrated that it had an effect on the common cold

A

Pleconaril

32
Q

____ and ____ are inhibitors of HCV NS5A protein

A

Sofosbuvir and dasabuvir.

33
Q

______ is is a carbocyclic nucleoside and is a agent acting against cytidine triphosphate synthetase

A

cyclopentenyl cytosine

34
Q

______ is a A is an analogue of cyclopentenyl cytosine and is a agent acting against S-adenosylhomocysteine hydrolase

A

3-Deazaneplanocin A

35
Q

_____ is a synthetic nucleoside that induces mutations in viral genes
dominant mechanism of action appears to be depletion of intracellular pools of GTP by inhibiting inosine-5′-monophosphate dehydrogenase
can also inhibit viral RNA-dependent RNA polymerase
used in combination to treat hepatitis C infection

A

Ribavirin

36
Q

______ is thet first effective antiviral drug to reach the clinic

inhibits viral protein synthesis

used to treat smallpox in the 1960s

worries about terrorism has led to new research for novel antiviral agents effective against smallpox

A

Methisazone

37
Q

______ are chemicals produced in the body which shut down infected host cells and limit the spread of virus.

A

Interferons

38
Q

True or False: The best broad-spectrum antiviral agents appear to work on a variety of targets, reducing the chances of resistance.

A

True

CH 456 Medicinal Chemistry (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions