Drug metabolism 1- mech Flashcards
1
Q
what are the two types of metabolism?
A
phase I
phase II
2
Q
what is phase I?
A
- is a functionalisation reaction produces or uncovers chemically reactive functional groups
- prepare drug for phase II reactions
3
Q
what are cytochrome p450 enzymes?
A
-oxidise anything due to Fe
- very non-polar, lipophilic
they are membrane bound monooxygenases in the the SER
-can accept many drugs into its active site not very specific enzyme
4
Q
what is the CYP450 enzyme structure like?
A
- heme group
- planar aromatic structure
- 4 nitrogens and fe complex in the middle
- work in association with a P450 reductase
5
Q
what are the 5 main processes needed for the catalytic cycle?
A
- substarte binding
- oxygen binding
- oxygen scission
- insertion of oxygen into the substrate
- release of product
6
Q
what happens when hydroxylation happens near a hetroatom?
A
leads to dealkylation forming a hemiacetal intermediate which is unstable
7
Q
whats more stable amide or esters?
A
amides
8
Q
how are epoxides generated?
A
by CYP450 activity?
9
Q
why is the generation of epoxides not a good thing?
A
because they are toxic cause they are very reactive they react with DNA and proteins
