functional groups

which functional groups increase the lipophilicity of drugs?

• nonpolar

  • alkyl groups

  • phenyl

  • halogen

  • ester

hydroxyl groups are …

a) strong polar

b) weak polar

c) non polar

a) strong polar

aliphatic amines are …

a) strong polar

b) weak polar

c) non polar

a) strong polar

tertiary amines have what type of interactions?

• dipole-dipole

quaternary amines use what type of interaction?

• ionic

  • charged molecule

carboxylic acid groups are …

a) strong polar

b) weak polar

c) non polar

b) weak polar

cyano groups are …

a) strong polar

b) weak polar

c) non polar

b) weak polar

nitro groups are ..

a) strong polar

b) weak polar

c) non polar

b) weak polar

amide groups are

a) strong polar

b) weak polar

c) non polar

b) weak polar

imide groups are

a) strong polar

b) weak polar

c) non polar

b) weak polar

sulfonamide groups are

a) strong polar

b) weak polar

c) non polar

b) weak polar

ether groups are

a) strong polar

b) weak polar

c) non polar

b) weak polar

what is this functional group?

• cyano

what is this functional group

nitro

what is this functional group?

• amide

what is this functional group?

• imide

what is this functional group?

• sulfonamide

what functional group is this?

• iso-propyl

what functional group is this?

• phenyl

what functional group is this?

• benzyl

polar functional groups have good (dissolution/absorption) but poor (dissolution/absorption)

• good dissolution

• poor absorption through the membrane

highly lipophilic functional groups have good (dissolution/absorption) but poor (dissolution/absorption)

• good absorption through membranes

• poor dissolution

what are the 4 functional groups that are considered as acidic functional groups (able to ionize in body fluids) ?

1. carboxylic group

2. imides

3. sulfonamides

4. phenolic

T/F: lower pKa values indicate stronger acidic functional groups

• true

what is the Henderson-Hasselbalch equation?

pKa = pH + log (proton carrying form/ proton missing form)

what is the pKa range for COOH?

• 3-5

what is the pKa range for sulfonamide, imide, and phenolic groups?

• 7-9

what type of amines are very strong polar groups?

• primary + secondary

if the drug name is as a salt with sodium or potassium or calcium or lithium, the drug is acidic or basic?

• acidic

if the drug name is as a salt with hydrochloride or sulfate or nitrate, the drug is acidic or basic?

• basic

if phenobarbital sodium has a pKa of 7.7, at pH 6, it is expected to be

a) 99-100% ionized

b) 90-100% non-ionized

c) 50-90% ionized

d) 10-50% ionized

e) 10-50% non-ionized

b) 90-100% non-ionized

• sodium = acidic

• non-ionized

• 10/1 → 10/11 × 100% = 90% unionized

• 100/1 → 100/101 × 100% = 99.99% unionized

phenobarbital has a pKa of 7. In a pH of 3, is it primarily ionized or unionized?

• phenobarbital = acidic because of imide

• primarily unionized

what are bases?

• donates electrons or accepts protons

lower pKb indicates stronger or weaker base?

• stronger

what are the basic functional groups?

1. aliphatic amines (primary, secondary, tertiary)

2. pyridine nitrogen

3. anilino nitrogen

aliphatic amines are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

e) strongly basic

pyridine type nitrogens are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

d) weakly basic

anilino type nitrogens are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

d) weakly basic

what is the pKb range of weakly basic functional groups?

• 7-9

what is the pKb range of strongly basic functional groups?

• 3-5

cyano (nitrile) type nitrogens are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

c) neutral

amides are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

c) neutral

pyrroles are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

c) neutral

what is the name of this functional group ?

• pyridine

what is the name of this functional group?

• aniline

quaternary ammonium nitrogens are are:

a) strongly acidic

b) weakly acidic

c) neutral

d) weakly basic

e) strongly basic

c) neutral

SATA: which of the following nitrogen groups are acidic functional groups?

a) sulfonamides

b) amides

c) imides

d) pyridines

e) pyrroles

a) sulfonamides

c) imides

what equation determines aromaticity?

• Huckle’s equation

Is this structure acidic, basic, or neutral?

• acidic

  • COOH = strongly acidic

Is this structure acidic, basic, or neutral?

• acidic

  • imide = acidic

If diltiazem, has a pka value of 7.7, how much of the drug will be available for absorption from the duodenum (pH 6.0)?

a. 0-10%

b. 10-50%

c. 50-90%

e. 99-100%

b. 10-50%

SATA: which of the following are basic nitrogen functional groups?

a) pyridine

b) pyrrole

c) nitrile

d) anilino

e) all of the above

a) pyridine

d) anilino

An aniline has a PKA of 3 and you are in a solution with a pH of 4.6, What percent of the substance will be unionized?

a. 50-90%

b. 99-99.9%

c. 90-99%

d. 50%

c. 90-99%

If the salt form of Phenobarbital is Phenobarbital Sodium, that would mean that Phenobarbital carries a ...

a. positive charge

b. negative charge

c. Neutral charge

b. negative charge

Identify the correct pairs:

i. Amide – Neutral Nitrogen

ii. Carboxylic Acids – polar and non-ionizable

iii. Nitro – Neutral Nitrogen

a. i and ii

b. i and iii

c. i only

d. iii only

e. i, ii and iii

b. i and iii

If ibuprofen has a pka of 4.5, how much of it will be dissociated in a pH of 2.5?

a. 99%

b. 99.9%

c. 0.1%

d. 1%

d. 1%