Drug 2- mech Flashcards
what is chlormethine and how does it work?
- it is a alkylating agent and it causes intrastrand and interstrand cross linking
- prevents replication
- mono-alkylation of guanine also possible
what is nitrogen mustard?
- known as chlormethine
- derived from sulfur mustards
- was invented as a 2nd world war chemical agent
where is the predominant crosslinks between which 2 species in nitrogen mustards?
N7 of guanine on twwo strands -an interstrand crosslink
what exactly does nitrogen mustard do?
stops enzymes such as dna POLYMERASE BEING ABLE TO SEPERATE THE STRANDS
what functional ring helps the nitrogen
benzene as it helps it become more controlled and less toxic due to electron being delocalised from N into aromatic ring so can control reactivity on the R group
what is cyclophosphamide and how does it work?
its the most commonly used alkylating agent
non-toxic prodrug orally active
what is busulfan and how does it work?
its a synthetic agent used as an anticancer agent
causes interstand crosslinking
what is dacarbazine and how does it work?
- its a prodrug activated in the liver
- it decomposes to form a methyldiazonium ion
- it methylates guanine groups
what is mitomycin c and how does it work?
- its a natural product its a alkylating agent
- one of the most toxic anticancer drug
what are metallating agents?
- they are similar to crosslinking
- usually with platinum
what is cisplatin and how does it work?
- its a prodrug
- its activated in the cell with low chloride ion conc
- binds to DNA in regions rich in guanine
- intrastrand links rather than interstrand
what are chain cutter?
they are agents which will induce DNA strand breaks
anticancer agent
generates radicals
what is bleomycins and hows does it work?
-binding with iron ions the amino groups bind to to reaction with oxygen to form radicals
prevents dna ligase from repairing damage
what are chain terminators?
-they mimic natural DNA bases
-missing 3’ prime
terminates synthesis of DNA and can inhibit the enzymes used in DNA replication
what is AZT and how does it work?
its a prodrug to treat HIV
its phosphorylated to triphosphate in the body
-it inhibits viral enzymes reverse transcriptase
what is topoisomerase poisons and how does it work?
- its double helix coil and has to unravel during replication
- unravelled leads to strain
- relieved by enzyme cutting and repair of DNA chain to prevent tangling
what are non-intercalating poisons
they stabilise the complex between DNA and topoisomerase enzyme
its an anticancer agents
causes chain cutting
what is camptothecin and how do they work?
stabilises complex between DNA and topoisomerase I
single strand breaks accumulate in the chain
what are quinolones and fluoroquinilones and and how do they work?
they are synthetic agents used as bacterial agents
- binding sites for agents revealed once DNA strands are “nicked”
- 4 drug molecules are stacked in the bound complex
