Medicinal Chemistry(physicochemical properties of drug molecules in relation to drug absorption,distribution,metabolism,and excretion)

Question 1

Determines the acid-base character of the drug.

Answer 1

Functional group
of drugs

Question 2

Drug properties that influence the absorption,excretion and compatibility with other drugs in a solution.

Answer 2

The acid -base properties of drugs

Question 3

Donates a proton on ionization to generate conjugate base(e.g. Aspirin) PH less than 7.

Answer 3

Acidic drugs

Question 4

Accepts a proton to generate a conjugate acid(e.g. Amphetamines)

Answer 4

Basic Drugs

Question 5

What decreases the basicity of a basic drug(eg.arylamines are less basic than alkylamine)

Answer 5

Delocalization of electrons from the nitrogen atoms.

Question 6

What drugs contain both acidic and basic functional groups

Answer 6

Amphoteric drugs

Question 7

Calculate the percentage of ionized and un-ionized forms of drugs at a given pH.
*allowing water solubility.Important determinant of absorption and excretion of drugs.

Answer 7

Relative acid strength (pKa)

Question 8

Ratio between the fraction of the drugs that dissolves in an organic phase and the fraction that distributes into an aqueous phase

Answer 8

Partition coefficient (Log P)
*log P of the drug

Question 9

Lipid layers with a lipophilic interior
*Drugs with high P values cross and absorbed rapidly
through passive diffusion from the GI tract

Answer 9

Biological Membranes

Question 10

sharing of electrons between an atom from the drug and an atom from the receptor.Strongest chemical bond.Irreversible.

Answer 10

covalent bond
*50-150kcal/mol

Question 11

AKA.Electrostatic interaction occurs between oppositely charged functional group on the drug and the receptor

Answer 11

ionic bond
* 5-10kcal/mol

Question 12

Is a bond in which hydrogen atoms serves as a bridge between two electronegative atoms.One from the drug and the other from the receptor

Answer 12

Hydrogen bond
*2-5kcal/mol

Question 13

Referred to as van der Waals forces or London forces.The interaction occurs between non polar regions of the drug and the receptor.Drugs should be close to the receptor for this to occur

Answer 13

Hydrophobic Interaction
*0.5-1kcal/mol

Question 14

Theory states that the binding of a drug(Agonist)to its receptor results in a conformational change in the receptor that initiate the pharmacological response whose magnitude is directly proportional to the number of receptor bound by the drug

Answer 14

Occupancy Theory

Question 15

States that the number of drug receptor per unit time determines the magnitude of the pharmacological response

Answer 15

Rate theory

Question 16

States that a receptor undergoes conformational change near a drug molecule to allow effective binding of the drug to the receptor

Answer 16

Induced fit theory

Question 17

Theory that is a combination of induced fit and rate theories.
Where agonist produce conformational change for pharmacological response;
*Antagoinist produce a non specific non conformational change.

Answer 17

Macromolecular perturbation theory

Question 18

States that receptors are always in a state of dynamic equilibrium between active and inactive states.
**Agonist shift the equilibrium of the in favor of the active state
***anatagonist prevent the activated state.

Answer 18

Activation aggregation theory