Med Chem of Antifungals

Question 1

“Fungins”

Answer 1

Echinocandins
- MoA: inhibit synthesis of B(1,3) glucan
- mammalian cells lack B(1,3) glucan

Question 2

Flucytosine + Amphotericin B

Answer 2

monitor Flucytosine levels b/c renal impairment can lead to flucytosine toxicity

Question 3

Azoles

Answer 3

• inhibit conversion of lanosterol to ergosterol
• functional group: 5-membered aromatic ring
• Inhibit other CYP450 drugs (inc [] of drugs metabolized by cyp // cyp inducers dec [azole])
• Rifampin is a CYP inducer

Question 4

Terbinafine

Answer 4

Allylamine
- MoA: inhibits squalene epoxidase

Question 5

Rezafungin

Answer 5

• MoA: inhibits B-glucan synthase enzyme

Question 6

Ibrexafungerp

Answer 6

• MoA: inhibits glucan synthase

Question 7

Fluconazole

Answer 7

• MoA: inhibition of 14 alpha-demethylase

Question 8

Amphotericin B

Answer 8

Polyenes
- MoA: binds to ergosterol
- Specific: mammalian cell membrane contain cholesterol
- Toxicity: renal damage (in almost all pts)
- Lipid Formulation dec Nephotoxicity/Infusion rxns

Question 9

Nystatin

Answer 9

Polyenes

Question 10

Tavaborole

Answer 10

• MoA: inhibits levcyl transfer RNA synthetase (LevRS)
• Boron is essential for activity

Question 11

Flucytosine

Answer 11

• MoA: inhibits thymidilate synthase
• converted to 5-FU; 5-FdUMP is a suicide inhibitor of thym synthase; no dTMP; no DNA snythesis
• mammalian cells are unable to convert fluc to active metabolite