Structural Properties 3 Lecture

Question 1

What is the acid-base theory?

Answer 1

Acid: proton donor
Base: proton acceptor
Influences absorption, excretion, drug-drug interactions, solubility, etc

Question 2

When an acidic FG looses a proton…?

Answer 2

It becomes negatively charged (conjugated base + ionized)

Question 3

When a basic FG gains a proton…?

Answer 3

it becomes positively charged (conjugate acid + ionized)

Question 4

What do ionized species participate in?

Answer 4

Ion-dipole interactions with water and enhance solubility

Question 5

Define amphoteric

Answer 5

Possess both acidic and basic properties

AKA: water

Question 6

Define pH

Answer 6

measure of the hydrogen ion concentration in solution

Question 7

What is phenol’s pH?

Answer 7

9-11

Question 8

What is alkyl carboxyylic acid’s pH?

Answer 8

5-6

Question 9

What is Aryl carboxylic acid’s pH?

Answer 9

4-5

Question 10

Lower the pKa…?

Answer 10

the stronger the acid

the weaker the base

Question 11

Inorganic vs organic?

Answer 11

Inorganic is stronger

Question 12

What is the strongest base?

Answer 12

Sodium hydroxide

Question 13

Saliva pH?

Answer 13

6.7-7.5

Question 14

Blood pH?

Answer 14

7.5

Question 15

Stomach pH?

Answer 15

1.0-3.5

Question 16

Intestine pH?

Answer 16

4.0-7.0

Question 17

Duodenum pH?

Answer 17

7.0-8.5

Question 18

Colon pH?

Answer 18

5.6-7.0

Question 19

CSF pH?

Answer 19

7.5

Question 20

Skin pH?

Answer 20

5.5

Question 21

Urine pH?

Answer 21

6.0

Question 22

What happens when a acid gives away its proton?

Answer 22

Whole molecule becomes charged

Question 23

When an acid or base is 50%…?

Answer 23

pH=pKa

Question 24

Strong acids and bases?

Answer 24

Completely dissociate in aqueous solutions such as the human body –> producing the respective conjugate acids and bases

Question 25

Acidic and basic functional groups?

Answer 25

Only dissociate to a certain extent

Question 26

What is the leveling effect?

Answer 26

Strong base will deprotonate water leaving OH
Strong acid will donate a proton to water leaving H30
What ever solvent you dissolve acid/base in, levels out the pH

Question 27

Ethanol and water?

Answer 27

Ethanol at physiological pH is no sufficientyly acidic enough to have a proton removed
Water is not sufficiently basic enough to remove a proton
“Neutral)

Question 28

Phenol at physiological pH?

Answer 28

NOT neutral because of stabilizing resonance

Question 29

H-A vs H-F

Answer 29

HA is weaker, loses the H easier

Question 30

What stabilizes increasing acidity?

Answer 30

EWG

- Because you can put a charge on it, better for balancing charge when you give away that H

Question 31

Henderson-Hasselbalch equation?

Answer 31

pH= pKa + log (base / acid)

degree of ionization

Question 32

What is physiological pH?

Answer 32

7.4

Question 33

Percent acid form equation?

Answer 33

acid form/ total * 100 = total unionized (acid) form allows us to predict the solubility and adsorption of a drug

Question 34

Define lipophilic

Answer 34

Water insoluble
Organic drug molecule that dissolves fully or partially in a non-aqueous or lipid solvent
Synonymous with hydrophobic

Question 35

Acidic drug the acid form is the?

Answer 35

unionized form

Question 36

pKa refers to?

Answer 36

conjugated acid

So equation = % ionized form

Question 37

For a basic drug the acid form is the?

Answer 37

ionized from

Question 38

Why inject a drug with a needle?

Answer 38

Directly into the blood stream

If swallowed less in the blood stream