MCMP 824: Lecture 2

Question 1

when we look at lipophilicity of a drug molecule and how that affects its effectiveness in a biological system, we observe this _____ relationship

Answer 1

parabolic

Question 2

when you reach an optimal Log P, this drug has ____ ____ required to cause a _____ ____

Answer 2

• minimum dosage

- biological effect

Question 3

ability to pass through membranes will be based on the

Answer 3

optimal lipophilicity AKA Log P

Question 4

if a drug molecule is too ______ it will not enter the membrane at all

Answer 4

hydrophilic (lipophobic)

Question 5

if a drug molecule is too _____ they get stuck within the membrane within the lipid bilayer

Answer 5

hydrophobic (lipophilic)

Question 6

Often times we don’t go through the trouble of measuring Log P. We instead use?

Answer 6

• calculate Log P (C logP)

Question 7

often times we don’t go through the trouble of measure Log P. We instead use calculated logP (C LogP) and ____ ____

Answer 7

pi values

Question 8

Pi values =

Answer 8

hydrophobic substituent constant

Question 9

a drug molecule can be broken down into fragments, and the overall calculated log P (C logP) is a ____ of ____ ____ of the molecules fragments

Answer 9

• sum of pi values

Question 10

pi values can be determined by _____ appropriated ___ ____ _____

Answer 10

• subtracting

- log P values

Question 11

the solubility of drugs usually ____ with the number of hydrogen bonds increases because?

Answer 11

• increases

- like dissolves like

Question 12

the water solubility of organic molecules generally increases with an increasing number of 1) ___ ____ and 2) ____ ____ _____

Answer 12

• hydrogen bonds

- ion-dipole interactions

Question 13

water is very polar so more dipole molecules or a carbonyl then can?

Answer 13

easily solvate those molecules

Question 14

soluble drugs consist of highly ____ _____ formed from: (3)

Answer 14

• dissociable salts

1) strong acids and strong bases
2) strong acids and weak bases
3) weak acids and strong bases

Question 15

often we have drug molecules that consist of soluble salts and they are generally formed with

Answer 15

strong acids and strong bases

Question 16

different salt forms can have different _______ : critical information of drugs and how they can have different properties

Answer 16

• solubilities

Question 17

the ionization state of a drug has an impact on the drug’s? (3)

Answer 17

1) site of absorption
2) extent of absorption (bioavailability)
3) activity at its receptor

Question 18

the Henderson-Hasselbach equation allows one to calculate?

Answer 18

the degree of ionization of a drug molecule at a specific pH

Question 19

which form do we want the drug to be in to be absorbed best?

Answer 19

UNIONIZED

Question 20

what is wrong with Log P?

Answer 20

doesn’t really take into effect whether a molecule is ionized or not

Question 21

so what will take into account whether a molecule is ionized or not?

Answer 21

Log D

Question 22

if a drug is an acid or base and is partitioned between two phases, and:

(1 + 2)

then the partition coefficient (P) should be converted to D or “effective Log P”

Answer 22

1) both the drug and its conjugate form are soluble in phase 1 (aqueous)
2) only the drug in in its uncharged form is soluble in phase 2 (organic)

Question 23

most drugs are absorbed in the ______ where the pH is between ?

Answer 23

• jejunum

- 5-7

Question 24

however, an acidic drug will tend to be absorbed in the ____ where the pH is generally ?

Answer 24

• stomach

- 1-3