Drugs Flashcards
Azidohymidine (AZT)
Anti-viral nucleoside analogue
Viral reverse transcriptase inhibitor
Terminates process due to lack of 3’ OH
used for HIV treatment
Didanosine (ddI)
Anti-viral nucleoside analogue
Viral reverse transcriptase inhibitor
Terminates process due to lack of 3’ OH
High affinity for prokaryotic cells
Acyclovir
Anti-viral nucleoside analogue
Viral reverse transcriptase inhibitor
Terminates process due to lack of 3’ OH
Is first phosphorylated by viral kinase and is only activated in infected cells
Tenofovir
Anti-viral nucleotide base analogue
Gets incorporated into newly formed HIV DNA and terminates synthesis
Cytosine arabinoside (Cytarabine)
AraC has a 3’ OH group to act as an acceptor for further chain elongation. However the OH gp at posn., 2 prevents polymerase adding the next dNTP due to stereo restraints causing chain termination.
Used for acute myeloid leukaemia.
Adenosine arabinoside (Vidarabine)
Planar configuration of arabinoside prevents DNA elongation despite 3’ OH being present.
Used for acute lymphoblastic leukaemia and herpes simplex infections
5-azacytidine, 5-aza-2’-deoxycytidine (Decitabine)
Under methylate DNA and inhibit DNA methyltransferase enzymes
Methylation of cytosine shuts down transcription
p15 tumor suppressor session
Ciproflaxin
inhibits DNA gyrase (topoisomerase II in eukaryotes) so DNA can’t unwind and replication is stopped
Actinomycin D
Inhibitor of replication
Intercalates between G-C bases
Prevent formation of regions of ss DNA
inhibits RNA transcription (prevents strand separation
Rifampin
Antibiotic from Streptomyces
Inhibits initiation of transcription
Blocks formation of first phosphodiester bond by binding to prokaryote RNA polymerase - doesn’t affect eukaryotic RNA polymerase
Used for TB treatment
Camptothecin
Inhibitor of eukaryotic replication
Inhibits topoisomerase I activity resulting in DNA breakage
Anti cancer drug
Etopside
inhibits activity of topoisomerase II
Anti-cancer drug
Alpha-amantin from Death Cap Mushroom
Inhibitor of RNA polymerase II
Tetracycline
Blocks elongation
Interacts with 30S sub unity of complete 70s ribosome
Prevent incoming aminoacyl-tRNA to access A site
Chloramphenicol
Inhibits prokaryotic elongation
Not used in developed countries - may inhibit mitochondrial ribosomes
Erythromycin
Macrolide structure
Binds to 50S subunit in complete ribosome
Blocks elongation by preventing ribosome movement relative to mRNA
Blocks ribosome translocation
Puromycin
structural analog to a portion of aminoacyl-tRNA
toxic to both prokaryotes and eukaryotes - not clnically useful
blocks elongation and causes peptide to fall out of ribosome P-site and causes premature translation termination
Cyclohexamide
simple organic molecule that inhibits elongation in eukaryotes - similar to choloramphenicol
extremely toxic to eukaryotes
widely used in laboratories
Streptomycin
Aminoglycoside
Binds to 30s ribosomal subunit
Distorts structure
Prevents assembly of complete ribosome and initiation
Acetazolamide
interferes with bicarbonate reabsorption into kidneys which reacidifies blood and alkalises urine
Aspirin
Acetylates a serene in channel of active site
Irreversibly inhibits cyclooxygenase (COX)
COX-1 (constitutive, physiologic functions)
COX-2 (inducible, pain, fever, inflammation)
DFP (do-isopropyl fluorophosphate)
Nerve gas poison, similar action as sarin
Irreversible inhibitor of acetylcholinesterase –> normally cleaves neurotransmitter acetylcholine in postsynaptic neuromuscular junction
Binds covalently to serene in active site
Leads to blurred vision, bronchoconstriction, seizures, respiratory arrest, and death
Statin drugs
HMG co-A reductase - catalyses synthesis step of cholesterol
Allopurinol
Drug is used as a substrate for xanthine oxidase and modified to an irreversible inhibitor
