Quinazolines belong to heterocyclic chemistry, also known as 1,3-naphthalenes. The backbone consists of two six-membered aromatic rings fused to each other, with two nitrogen atoms at positions 1 and 3 on the backbone. The presence of these two nitrogen atoms in quinazoline increases its importance in pharmaceutical and biological reactions. Quinazolines and their derivatives are among the most important heterocyclic compounds due to their diverse chemical reactivity and important range of biological activities.
Pyrazoline is a heterocyclic chemical compound with the molecular formula C3H6N2. Pyrazolines are well-known and important nitrogen-containing five-membered ring heterocyclic compounds. Pyrazoline derivatives have numerous prominent pharmacological effects, such as antimicrobial, anti-inflammatory, analgesic, antidepressant and anticancer.