Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
37 Cards in this Set
- Front
- Back
|
what does QSAR stand for? |
Quantitative structure–activity relationship |
|
|
what is the aim of QSAR? |
|
|
|
what do you need to perform QSAR? |
quantitative measurements for biological and physicochemical properties |
|
|
what are the most common physicochemical properties studied |
-hydrophobicity of the molecule/substituent -electronic properties of substituents -steric properties of substituents |
|
|
what is the partition coefficient (P) |
P= [drug in octanol]/[drug in water] |
|
|
a high P gives ____ hydrophobicity |
high |
|
|
as log P increases binding _________ |
increases |
|
|
binding is greater for polar or non-polar drugs |
non polar |
|
|
sigma in QSAR |
electronic effects- hammett substituent constant |
|
|
pi in QSAR |
|
|
|
what logP do you need to get into the CNS |
2.3 |
|
|
if you don't want the drug to go into the CNS.. you want to change the log P value away from ___ |
2 |
|
|
positive pi values are _____ hydrophobic than H |
positive pi values are more hydrophobic than H |
|
|
negative pi values are _____ hydrophobic than H |
negative pi values are less hydrophobic than H |
|
|
difference between P and pi |
P measures molecule's overall hydrophobicity but pi identifies specific regions of molecule that might interact with hydrophobic regions in the binding site |
|
|
what is the equation to find sigma |
|
|
|
how do you find KH (for finding sigma) |
KH = [products]/[reactants] |
|
|
if X is an electron-donating group (CH3) what is sigma -/+? |
sigma is negative: less dissociation, the charge is destabilized! |
|
|
if X is an electron-withdrawing group (NO2) what is sigma -/+? |
sigma is positive: charge is stabilized by the electron-withdrawing group |
|
|
meta/para/ortho do they have an effect on sigma? |
only meta and para |
|
|
does the sigma value depend on inductive and resonance effects |
yes the sigma value depends on inductive and resonance effects |
|
|
does meta have resonance effects? |
no, only para |
|
|
T/F e-withdrawing substituents decrease activity |
F- e-withdrawing substituents increase activity |
|
|
the electronic factor R quantifies a substituent's ____ effects |
resonance effects |
|
|
the electronic factor F quantifies a substituent's ____ effects |
inductive effects |
|
|
when you have an electron donating group the rate ________ |
electron donating group makes the rate decrease |
|
|
when you have an electron withdrawing group the rate ________ |
electron withdrawing group makes the rate increase |
|
|
under basic conditions, the rate is affected by what |
steric and electronic factors |
|
|
under acidic conditions, the rate is affected by what |
steric factors only |
|
|
the taft steric factor (Es) is measured by what equation? and under what conditions? |
Es=log kx - log k0 |
|
|
what does molar refractivity (MR) measure? |
a substituents volume |
|
|
what is the equation for molar refractivity (MR) |
|
|
|
Activity is increased when pi is (+/-)? and sigma is (+/-)? |
pi is positive = hydrophobic substituents sigma is negative = e-donating substituents |
|
|
to get drug to the site of action. lipophilicity or electronic factors |
lipophilicity- to get drug to the site of action |
|
|
at the site of action. lipophilicity or electronic factors |
electronic factors- at the site of action |
|
|
log 1/c gives the _____ |
potency |
|
|
what are the three possible outcomes for the topliss decision tree |
1) more potent (M) than parent |
