RWD - Medicinal chemistry Flashcards
What is a prodrug?
A biologically inactive compound which can be metabolized in the body to produce a drug.
Drug latentiation is…
… the chemical modification of a biologically active compound to form a new compound, which in vivo will liberate the parent compound either via enzymatic or non enzymatic reactions (chemical hydrolysis, dissociation etc.)
Why do we need pro-drugs?
- Not absorbed from GI tract due to polarity, or not through skin or BBB
- The drug may be unstable
- Drug may cause toxicity
- So it can be metabolised at site of action
- Lack of site specificity
- Formulation problems
- Water insoluble
Name three water soluble B vitamins.
Vit B 1 - thiamine
Vit B 2 - riboflavine
Vit B 6 - pyridoxine
Although water soluble B vitamins are actively absorbed, what is the problem with this?
Active absorption can easily be inhibited or saturated.
No quaternary N results in?
good absorption into GI tract
What are some factors that affect dermal absorption?
Basically factors that affect skin hydration:
- presence of urea
- vehicle formation
Benefits of sustained/ prolonged release of drugs
- reduces risk of toxicity
- avoids peak and valley effects seen with fast release drugs
- improves patient compliance
- avoids night time dosing
- can reduce total amount of drug needed
- reduces incidence of GI side effects
- reduces frequency of doses needed to be given
Activity depends not only on the ____ of the drug but also the _____ of the pro-drug into active form
release
metabolism
Carbamate ester prevents _____ s that most of the dose reaches the liver intact.
Hydrolysis
Precipitation at injection site leads to _______ absorption
delayed
Advantages of parenteral administration?
- quick blood levels obtained
- allows delivery when oral therapy not feasible
- efficient delivery, especially for drug testing
If a drug is only sparingly stable in an aqueous injectable, it can be presented as a…..
reconstitutable powder.
