Five membered heterocyclic compound with two hetero atom. two nitrogen atom adjacent to each other in a ring structure

1. Hetrocyclic compound - Pyrazole
Lecture by
S.Mathivanan.,M.Pharm
Asst professor
Pharmacy

2. Pyrazole
• Pyrazole is the name given by “LUDWIG
KNORR” to this class of compounds in 1883.
• The simple doubly unsaturated compound
containing two nitrogen and three carbon
atoms in the ring, with the nitrogen atoms
neighboring, is known as pyrazole.

3. History
• For a long time no pyrazole derivative had
been found in nature, but in 1959 β-(1-
pyrazolyl) alanine was isolated from the seeds
of water melons (Citurllus lanatus) (L.
Fowden).

4. • 3-n-nonylpyrazole is the first natural pyrazole
thta has been obtained from a plant
Houttuynia cordata which belongs to the
family Piperaceae. This compounds exhibit
anti-microbial property

5. Analogues of Pyrazole
Pyrazole Pyrazoline Pyrazolidine
5-Pyrazolinone 3,5-Pyrazolidinedione Imidazole (will discuss later)

6. Physical properties
• Crystalline solid
• Pyridine like odour
• Bitter taste
• Melting point 70°C
• Boiling point 187°C
• Soluble in water and organic solvents.

7. Chemical properties

10. Synthesis of Pyrazole

15. Reactions of Pyrazole

23. Medicinal uses of Pyrazole

25. • Sulfaphenazole : Sulphonamide antibiotic.
Used for treating cough and allergy
• Celecoxib : NSAID . Used to treat arthritis,
pain, menstrual cramps, and colonic polyps.

30. Thank you..!!!