general

1. Antimalerial Drugs
BY
Umesh D. Joshi

2. Continued..

3. Life Cycle of Malerial parasite

15. MOA
• Intercalation of DNA : Quinine, chloroquine intercalate
the DNA but concenration of drug needed high.
• Weak base hypothesis : these drugs accumulate in food
vacuole of parasite which inhibits parasitic digestive
enzymes involved in hemoglobin degradation.conc.
Needed high of drug for activity.
• Interaction between drug and FPIX complex:parasite
obtaining amino acids from hemoglobin for growth. If
this complex is unbound form is toxic to parasite since
it generate active oxygen which destroys cell of
parasite.parasite having defence mechanism to convert
FPIX complex by enzyme hempolymerase to hematin
which is non toxic to parasite which forms hemozoin
pigment these drugs bind to the complex and prevent
polymerization. This results in destruction of parasite.

27. SAR pyrimethamine

28. MOA

31. SAR

34. SAR Continued..

38. Quinacreine structure

39. SAR

43. Halofantriene
• MOA is similar to chloroquine, Amodiaquine
form toxic complexes with ferritoporphyrin IX
that damage cell membrane of parasite.