Module 4 (Exam II)

Question 1

Describe the two most common reactions pertinent to metabolism.

Answer 1

1. Hydrolysis (esters, amides, & nitriles)
2. REDOX reactions (CYP450’s in liver)

Question 2

What are the 4 areas of drug excretion?

Answer 2

1. Kidneys
2. Feces (via bile)
3. Lungs (inhaled anesthetics)
4. Sweat (uncommon)

Question 3

Why do most drugs fail during their discovery phase?

Answer 3

Poor Pharmacokinetics

Question 4

___% of all drugs fail in clinical testing.

Answer 4

90

Question 5

What is the Lipinksi rule of 5 utilized for?

Answer 5

• Describes a drug’s potential as a NCE (new chemical entity)
• Measures the NCE’s bioavailability

Question 6

What metrics comprise the Lipinksi Rule of 5

Answer 6

• ≤ 5 hydrogen bond donors (amines & alcohols)
• ≤ 10 hydrogen bond acceptors (Total: O, N, F)
• MW less than 500g/mol
• cLogP ≤ 5

Question 7

What is cLogP?
What would an increased cLogP denote?
How about a decreased cLogP?

Answer 7

Calculated Partition Coefficient
↑ = lipophillic. ↓ = hydrophillic

Question 8

Low MW drugs with a high cLogP can easily cross membranes. T/F?

Answer 8

False, Low MW w/ low cLogP needed to cross membranes.

needs verification

Question 9

Which 5 functional groups have been linked to increased toxicity due to their metabolites?

Answer 9

1. Aromatic Anilines
2. Nitroaromatics
3. Aliphatic Halides
4. Polycyclic Aromatic Hydrocarbons
5. Thiophenes

Question 10

What functional group was linked to testicular cancer in chimney sweeps?

Answer 10

Polycyclic Aromatic Hydrocarbons

Question 11

Differentiate strong acids & weak acids?

Answer 11

Strong acids completely dissociate in H₂O
Weak acids partially dissociate in H₂O

Question 12

Strong acids have _____ conjugate bases.

Answer 12

weak

Question 13

Equilibrium favors the ______ acid.

Answer 13

weaker

Question 14

Water is amphoteric, meaning what?

Answer 14

It can act as either an acid or a base.

Question 15

What is molarity?

Answer 15

Mol solute / L solution

Question 16

What is Molality?

Answer 16

Mol of solute / kg of solvent

Question 17

What is weight percent?

Answer 17

(mass of solute/ mass of solution) · 100

Question 18

What is volume percent?

Answer 18

(volume of solute/ volume of solution) · 100

Question 19

What is a Dalton?

Answer 19

g/mol

Question 20

What drugs require active transport?

Answer 20

Ionized drugs

Question 21

What drugs do not require active transport?

Answer 21

• Small drugs (<50 Da) - bulk flow
• Lipophillic drugs (50 - 500 Da) - passive transport.

Question 22

What forces allow a drug to bind to its active site?

Answer 22

Intermolecular forces

Question 23

Shorter bond length means ______ strength.

Answer 23

more

Question 24

What are the intermolecular forces in order of weakest to strongest?

Answer 24

1. Van-Der-Waals
2. Dipole-Dipole
3. Hydrogen Bonding
4. Ion-Dipole
5. Electrostatic
6. Covalent bonds

Question 25

What characterizes van der Waals forces?

Answer 25

- Two non-polar molecules - Most common intermolecular force

Question 26

What characterizes dipole-dipole forces?

Answer 26

- Occurs in all polar molecules - Strength depends on individual dipoles

Question 27

What characterizes hydrogen-bonding forces?

Answer 27

- Specialized Dipole-Dipole between an H-bond donor and H-bond acceptor.

Question 28

What are the strongest Hydrogen-bond acceptors?

Answer 28

- O, N, & F

Question 29

What is the most important intermolecular force pertaining to drug-receptor binding?

Answer 29

- Hydrogen bonding

Question 30

What characterizes an Ion-Dipole force?

Answer 30

- Interaction between a full formal charge (ex. Na⁺) and a dipole (ex. H₂O)

Question 31

What characterizes electrostatic interaction forces?

Answer 31

- Cation & Anion interacting