EXAM 2 - Functional Groups in Drug Molecules (part 2) Flashcards
Describe amines and their properties.
Key interactions:
Role for solubility:
Metabolism:
Significant acid-base:
Chemical reactivity:
-
Characterized by what the nitrogen is bound to.
(primary amine - N bound to one carbon)
Key interactions: H-bond acceptor or donor
(donor - as long as there is a hydrogen bound to it)
Role for solubility: increase water solubility (H-bonding)
Metabolism: complex; mainly oxidation (replace amine with oxygen)
Significant acid-base: weak base (significantly ionized at ph 7)
Chemical reactivity: reacts as nucleophiles
Why are anilines less basic than ordinary amines?
Anilines are less basic because of resonance
- the lone pair of electrons on the nitrogen is not available to interact with the acids (ring structure) because they are delocalized
A. Secondary; Hydrogen bond donating AND accepting
Ethers and Acetals Overview
Key interactions:
Role for solubility:
Metabolism:
Significant acid-base:
Chemical reactivity:
Key interactions: H-bond acceptors at oxygen lone pair, dipole interactions
Role for solubility: slightly increase water solubility
Metabolism: very little if stable
Significant acid-base: none
Chemical reactivity:
* hemiacetal - very unstable; reversible (can convert to aldehyde or alcohol)
* acetal - stable; reversible (can convert to aldehyde or alcohol)
* ethers - very stable; not prone to nucleophilic attack
What are epoxides?
A special type of ether
* highly strained
* very prone to ring opening
* very electrophilic
What makes a hemiacetal? hemiketal?
Hemiacetal - aldehyde attached to an alcohol
Hemiketal - ketone attached to an alcohol
* Only stable in cyclic systems
D. 1= hemiacetal, 2 = ketal, 3 = acetal
Draw an acetal group.
Draw a ketal group.
Draw a hemiacetal.
Draw a hemiketal.
Carbonyl derivatives overview
Key interactions:
Role for solubility:
Metabolism:
Significant acid-base:
Chemical reactivity:
Key interactions: H-bond acceptor at carbonyl oxygen, donor only with amide N-H, dipole-dipole interactions
Role for solubility: increases water solubility
Metabolism: reduction or hydrolysis
Significant acid-base: slightly basic
Chemical reactivity: fairly reactive toward nucleophillic attack bc of electrophilic carbonyl carbon
How does the electrophilicity of carbonyl carbon change depending on funcitonal groups?
O is nucleophilic and C is electrophilic
Withdrawing groups on C -
* increase electrophilicity of carbonyl carbon
* decrease nucleophilicity of O
Donor groups on C -
* decrease electrophilicity on C
* increase nucleophilicity of O
Are aldehydes usually found in drugs?
No. They are rare in drugs
* very sensitive to oxidation
Are ketones rare?
Are they stable?
Ketones are very common in drugs and are very stable.
Draw an ester.
C. Prone to hydrolysis
